Fcc Grol Element 3

Front 1

The product of the readings of an AC voltmeter and AC ammeter is called:
A. Apparent power.
B. True power.
C. Power factor.
D. Current power.

Back 1

A. Apparent power.

Front 2

What is the basic unit of electrical power?
A. Ohm.
B. Watt.
C. Volt.
D. Ampere.

Back 2

B. Watt.

Front 3

What is the term used to express the amount of electrical energy stored in an electrostatic field?
A. Joules.
B. Coulombs.
C. Watts.
D. Volts.

Back 3

A. Joules

Front 4

What device is used to store electrical energy in an electrostatic field?
A. Battery.
B. Transformer.
C. Capacitor.
D. Inductor.

Back 4

C. Capacitor.

Front 5

What formula would determine the inductive reactance of a coil if frequency and coil inductance are known?
A. X(sub L) = πfL
B. X(sub L) = 2πfL
C. X(sub L) = 1/2πfL
D. X(sub L) = 1/R2+X2

Back 5

B. X(sub L) = 2πfL

Front 6

What is the term for the out-of-phase power associated with inductors and capacitors?
A. Effective power.
B. True power.
C. Peak envelope power.
D. Reactive power.

Back 6

D. Reactive power.

Front 7

What determines the strength of the magnetic field around a conductor?
A. The resistance divided by the current.
B. The ratio of the current to the resistance.
C. The diameter of the conductor.
D. The amount of current.

Back 7

D. The amount of current.

Front 8

What will produce a magnetic field?
A. A DC source not connected to a circuit.
B. The presence of a voltage across a capacitor.
C. A current flowing through a conductor.
D. the force that drives current through a resistor.

Back 8

C. A current flowing through a conductor.

Front 9

When induced currents produce expanding magnetic fields around conductors in a direction that opposes the original magnetic field, this is known as:
A. Lenz's law.
B. Gilbert's law.
C. Maxwell's law.
D. Norton's law.

Back 9

A. Lenz's law.

Front 10

The opposition to the creation of magnetic lines of force in a magnetic circuit is known as:
A. Eddy currents.
B. Hysteresis.
C. Permeability.
D. Reluctance.

Back 10

D. Reluctance.

Front 11

What is meant by the term "back EMF"?
A. A current equal to the applied EMF.
B. An opposing EMF equal to R times C (RC) percent of the applied EMF.
C. A voltage that opposes the applied EMF.
D. A current that opposes the applied EMF.

Back 11

C. A voltage that opposes the applied EMF.

Front 12

Permeability is defined as:
A. The magnetic field created by a conductor wound on a laminated core and carrying current.
B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it.
C. Polarized molecular alignment in a ferromagnetic material while under the influence of a magnetizing force.
D. None of these.

Back 12

B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it.

Front 13

What metal is usually employed as a sacrificial anode for corrosion control purposes?
A. Platinum bushing.
B. Lead bar.
C. Zinc bar.
D. Brass rod.

Back 13

C. Zinc bar.

Front 14

What is the relative dielectric constant for air?
A. 1
B. 2
C. 4
D. 0

Back 14

A. 1

Front 15

Which metal object may be least affected by galvanic corrosion when submerged in seawater?
A. Aluminum outdrive.
B. Bronze through-hull.
C. Exposed lead keel.
D. Stainless steel propeller shaft.

Back 15

D. Stainless steel propeller shaft.

Front 16

Skin effect is the phenomenon where:
A. RF current flows in a thin layer of the conductor, closer tot he surface, as frequency increases.
B. RF current flows in a thin layer of the conductor, closer to the surface, as frequency decreases.
C. Thermal effects on the surface of the conductor increase the impedance.
D. Thermal effects on the surface of the conductor decrease the impedance.

Back 16

A. RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases.

Front 17

Corrosion resulting from electric current flow between dissimilar metals is called:
A. Electrolysis.
B. Stray current corrosion.
C. Oxygen starvation corrosion.
D. Galvanic corrosion.

Back 17

D. Galvanic corrosion.

Front 18

Which of these will be most useful for insulation at UHF frequencies?
A. Rubber.
B Mica.
C. Wax impregnated paper.
D. Lead.

Back 18

B. Mica

Front 19

What formula would calculate the total inductance of inductors in series?
A. L(sub T) = L(sub 1)/L(sub 2)
B. L(sub T) = L(sub 1) + L(sub 2)
C. L(sub T) = 1/L(sub1)+L(sub 2)
D. L(sub T) = 1/L(sub1)xL(sub 2)

Back 19

B. L(sub T) = L(sub 1) + L(sub 2)

Front 20

Good conductors with minimum resistance have what type of electrons?
A. few free electrons.
B. No electrons.
C. Some free electrons.
D. Many free electrons.

Back 20

D. Many free electrons.

Front 21

which of the 4 groups of metals listed below are the best low-resistance conductors?
A. Gold, silver, and copper.
B. Stainless steel, bronze, and lead.
C. Iron, lead and nickel.
D. Bronze, zinc, and manganese.

Back 21

A. Gold, silver, and copper.

Front 22

What is the purpose of a bypass capacitor?
A. It increases the resonant frequency of the circuit.
B. It removes direct current from the circuit by shunting DC to ground.
C. It removes alternating current by providing a low impedance path to ground.
D. it forms part of an impedance transforming circuit.

Back 22

C. It removes alternating current by providing a low impedance path to ground.

Front 23

How would you calculate the total capacitance of three capacitors in parallel?
A.C(sub T) = C(sub 1) + C(sub 2)/C(sub 1) - C(sub 2) +C(sub 3)
B. C(sub T) = C(sub 1) + C(sub 2) +C(sub 3)
C. C(sub T) = C(sub 1) + C(sub 2)/C(sub 1) x C(sub 2) +C(sub 3)
D.C(sub T) = 1/C(sub 1) + 1/C(sub 2) + 1/C(sub 3)

Back 23

B. C(sub T) = C(sub 1) + C(sub 2) +C(sub 3)

Front 24

How might you reduce the inductance of an antenna coil?
A. Add additional turns.
B. Add more core permeability.
C. Reduce the number of turns.
D. Compress the coil turns.

Back 24

C. Reduce the number of turns.

Front 25

What are the two most commonly-used specifications for a junction diode?
A. Maximum forward current and capacitance.
B. Maximum reverse current and PIV (peak inverse voltage).
C. Maximum reverse current and capacitance.
D. Maximum forward current and PIV (peak inverse voltage).

Back 25

D. Maximum forward current and PIV (peak inverse voltage).

Front 26

What limits the maximum forward current in a junction diode?
A. The peak inverse voltage (PIV).
B. The junction temperature.
C. the forward voltage.
D. The back EMF.

Back 26

B. The junction temperature.

Front 27

MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages:
A. Schottky diode.
B. metal oxide varistor (MOV).
C. Zener diode.
D. Tunnel diode.

Back 27

C. Zener diode.

Front 28

What are the two basic types of junction field-effect transistors?
A. N-channel and P-channel.
B. High power and low power.
C. MOSFET and GaAsFET.
D. Silicon FET and germanium fet.

Back 28

A. N-channel and P-channel.

Front 29

A common emitter amplifier has:
A. Lower input impedance than a common base.
B. More voltage gain than a common collector.
C. Less current gain than a common base.
D. Less voltage gain than a common collector.

Back 29

B. More voltage gain than a common collector.

Front 30

How does the input impedance of a field-effect transistor compare with that of a bipolar transistor?
A. An FET has high input impedance; a bipolar transistor has low input impedance.
B. One cannot compare input impedance without first knowing the supply voltage.
C. an FET has low input impedance; a bipolar transistor has high input impedance.
D. The input impedance of FETs and bipolar transistors is the same.

Back 30

A. An FET has high input impedance; a bipolar transistor has low input impedance.

Front 31

An AC ammeter indicates:
A. Effective (TRM) values of current.
B. Effective (RMS) values of current.
C. Peak values of current.
D. Average values of current.

Back 31

B. Effective (RMS) values of current.

Front 32

By what factor must the voltage of an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the peak voltage value?
A. 0.707
B. 0.9
C. 1.414
D. 3.14

Back 32

C. 1.414

Front 33

What is the RMS voltage of a common household electrical power outlet?
A. 331-V AC
B. 82.7-V AC
C. 165.5-V AC
D. 117-V AC

Back 33

D. 117-V AC

Front 34

What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an oscilloscope?
A. Peak-to-peak.
B. RMS.
C. Average.
D. DC.

Back 34

A. Peak-to-peak.

Front 35

By what factor must the voltage measured in an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the average voltage value?
A. 0.707
B. 1.414
C. 0.9
D. 3.14

Back 35

C. 0.9

Front 36

What is the peak voltage at a common household electrical outlet?
A. 234 volts.
B. 117 volts.
C 331 volts.
D. 165.5 volts.

Back 36

D. 165.5 volts.

Front 37

What is the sine wave?
A. A constant-voltage, varying-current wave.
B. A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed.
C. A wave following the laws of the trigonometric tangent function.
D. A wave whose polarity changes in a random manner.

Back 37

B. A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed.

Front 38

How many degrees are there in one complete sine wave cycle?
A. 90 degrees.
B. 270 degrees.
C.180 degrees.
D. 360 degrees.

Back 38

D. 360 degrees.

Front 39

What type of wave is made up of sine waves of the fundamental frequency and all the odd harmonics?
A. Square.
B. Sine.
C. Cosine.
D. Tangent.

Back 39

A. Square.

Front 40

What is the description of a square wave?
A. A wave with only 300 degrees in one cycle.
B. A wave whose periodic function i s always negative.
C. A wave whose periodic function is always positive.
D. A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time.

Back 40

D. A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time.

Front 41

What type of wave is made up of sine waves at the fundamental frequency and all the harmonics?
A. Sawtooth wave.
B. Square wave.
C. Sine wave.
D. Cosine wave.

Back 41

A. Sawtooth wave.

Front 42

What type of wave is characterized by a rise time significantly faster than the fall time (or vice versa)?
A. Cosine wave.
B. Square wave.
C. Sawtooth wave.
D. Sine wave.

Back 42

C. Sawtooth wave.

Front 43

What is the term used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage?
A. Cosine voltage.
B. Power factor.
C. Root mean square (RMS).
D. Average voltage.

Back 43

C. Root mean square (RMS).

Front 44

What happens to reactive power in a circuit that has both inductors and capacitors?
A. It is dissipated as heat in the circuit.
B. It alternates between magnetic and electric fields and is not dissipated.
C. It is dissipated as inductive and capacitive fields.
D. It is dissipated as kinetic energy within the circuit.

Back 44

B. It alternates between magnetic and electric fields and is not dissipated.

Front 45

Halving the cross-sectional area of a conductor will:
A. Not affect the resistance.
B. Quarter the resistance.
C. Double the resistance.
D. Halve the resistance.

Back 45

C. Double the resistance.

Front 46

Which of the following groups is correct for listing common materials in order of descending conductivity?
A. Silver, copper, aluminum, iron, and lead.
B. Lead, iron, silver, aluminum, and copper.
C. Iron, silver, aluminum, copper, and silver.
D. Silver, aluminum, iron, lead, and copper.

Back 46

A. Silver, copper, aluminum, iron, and lead.

Front 47

How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase?
A. Multiply RMS voltage time RMS current.
B. Subtract apparent power from the power factor.
C. Divide apparent power by the power factor.
D. Multiply apparent power times the power factor.

Back 47

D. Multiply apparent power times the power factor.

Front 48

Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when:
A. The load impedance is greater than the source impedance.
B. The load impedance equals the internal impedance of the source.
C. The load impedance is less than the source impedance.
D. The fixed values of internal impedance are not relative to the power source.

Back 48

B. The load impedance equals the internal impedance of the source.

Front 49

What value of circuit resistance would be needed to obtain a full scale deflection on a 50 microamp DC meter with an applied voltage of 200 volts DC?
A. 4 megohms
B. 2 megohms
C. 400 kilohms
D. 200 kilohms.

Back 49

A. 4 megohms

Front 50

Which of the following Ohms Law formulas is incorrect?
A. I = E/R
B. I = R/E
C. E = I x R
D. R = E/I

Back 50

B. I = R/E

Front 51

If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor?
A. 25 volts
B. 52 volts
C. 200 volts
D. 100 volts

Back 51

D. 100 volts

Front 52

If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor?
A. 2 amperes
B. 1 ampere
C. 300 amperes
D. 20,000 amperes

Back 52

A. 2 amperes

Front 53

If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance?
A. 3 ohms
B. 30 ohms
C. 93 ohms
D. 270 ohms

Back 53

B. 30 ohms

Front 54

A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 VDC?
A. 150 ohms
B. 220 ohms
C. 380 ohms
D. 470 ohms

Back 54

C. 380 ohms

Front 55

What is the peak-to-peak RF voltage on the 50 ohm output of a 100 watt transmitter?
A. 70 volts
B. 100 volts
C. 140 volts
D. 200 volts

Back 55

D. 200 volts

Front 56

What is the maximum DC or RMS voltage that may be connected across a 20 watt, 2000 ohm resistor?
A. 10 volts
B. 100 volts
C. 200 volts
D. 10,000 volts

Back 56

C. 200 volts

Front 57

A 500-ohm, 2-watt resistor and a 1500-ohm, 1-watt resistor are connected in parallel. What is the maximum voltage that can be applied across the parallel circuit without exceeding wattage requirements?
A. 22.4 volts
B. 31.6 volts
C. 38.7 volts
D. 875 volts

Back 57

B. 31.6 volts

Front 58

What is the voltage drop across R(1) if 10V source with R(1) 300 ohms in parallel with R(2) 200 ohms and R(3) 100 ohms?
A. 9 volts
B. 7 volts
C. 5 volts
D. 3 volts

Back 58

C. 5 volts

Front 59

What is the voltage drop across R(1) if 12V source with 3V zener diode is in parallel with R(1) 10K ohms and R(2) 10K and R(3) 5K?
A. 1.2 volts
B. 2.4 volts
C. 3.7 volts
D. 9 volts

Back 59

D. 9 volts

Front 60

What is the maximum rated current-carrying capacity of a resistor marked "2000 ohms, 200 watts"?
A. 0.316 amps
B. 3.16 amps
C. 10 amps
D. 100 amps

Back 60

A. 0.316 amps

Front 61

What is the most the actual transmit frequency could differ from a reading of 462,100,000 hertz on a frequency counter with a time base accuracy of +- 0.1ppm?
A. 46.21 Hz
B. 0.1 MHz
C. 462.1 Hz
D. 0.2 Mhz

Back 61

A. 46.21 Hz

Front 62

The second harmonic of a 380 kHz frequency is:
A. 2 MHz
B. 760 kHz
C. 190 kHz
D. 144.4 GHz

Back 62

B. 760 kHz

Front 63

What is the second harmonic of SSB frequency 4146 kHz?
A. 8292 kHz
B. 4.146 MHz
C. 2073 kHz
D. 12438 kHz

Back 63

A. 8292 kHz

Front 64

What is the most the actual transmitter frequency could differ from a reading of 156,520,000 hertz on a frequency counter with a time base accuracy of +- 1.0 ppm?
A. 165.2 Hz
B. 15.652 kHz
C. 156.52 Hz
D. 1.4652 MHz

Back 64

C. 156.52 Hz

Front 65

What is the most the actual transmitter frequency could differ from a reading of 156,520,000 hertz on a frequency counter with a time base accuracy of +- 10 ppm?
A. 146.52 Hz
B. 1565.20 Hz
C. 10 Hz
D. 156.52 kHz

Back 65

B. 1565.20 Hz

Front 66

What is the most the actual transmitter frequency could differ from a reading of 462,100,000 hertz on a frequency counter with a time base accuracy of +- 1.0 ppm?
A. 46.21 MHz
B. 10 Hz
C. 1.0 MHz
D. 462.1 Hz

Back 66

D. 462.1 Hz

Front 67

At pi/3 radians, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts
B. -2.5 volts
C. +2.5 volts
D. +4.3 volts

Back 67

D. +4.3 volts

Front 68

At 150 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts
B. -2.5 volts
C. +2.5 volts
D. +4.3 volts

Back 68

C. +2.5 volts

Front 69

At 240 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts
B. -2.5 volts
C. +2.5 volts
D. +4.3 volts

Back 69

A. -4.3 volts

Front 70

What is the equivalent to the root-mean-square value of an AC voltage?
A. AC voltage is the square root of the average AC value.
B. The DC voltage causing the same heating in a given resistor at the peak AC voltage.
C. The AC voltage found by taking the square of the average value of the peak AC voltage.
D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value.

Back 70

D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value.

Front 71

What is the RMS value of a 340-volt-peak-to-peak pure sine?
A. 170 volts AC
B. 240 volts AC
C. 120 volts AC
D. 350 volts AC

Back 71

C. 120 volts AC

Front 72

Determine the phase relationship between the two signals.(B starts at A's 90 degree mark.)
A. A is lagging B by 90 degrees
B. B is lagging A by 90 degrees
C. A is leading B by 180 degrees
D. B is leading A by 90 degrees

Back 72

B. B is lagging A by 90 degrees

Front 73

What is the power factor equal in an R-L circuit having a 60 degree phase relationship between the voltage and the current?
A. 0.414
B. 0.866
C. 0.5
D 1.73

Back 73

C. 0.5

Front 74

If a resistance to which a constant voltage is applied is halved, what power dissipation will result?
A. Double
B. Halved
C. Quadruple
D. Remain the same

Back 74

A. Double

Front 75

746 watts corresponding to the lifting of 550 pounds at the rate of on-foot-per-second, is the equivalent of how much horsepower?
A. One-quarter horsepower
B. One-half horsepower
C. Three-quarter horsepower
D. One horsepower

Back 75

D. One horsepower

Front 76

In a circuit where the AC voltage and current are out of phase, how can the true power be determined?
A. By multiplying the apparent power times the power factor.
B. By subtracting the apparent power from the power factor.
C. By dividing the apparent power by the power factor.
D. By multiplying the RMS voltage times the RMS current.

Back 76

A. By multiplying the apparent power times the power factor.

Front 77

What does the power factor equal in an R-L circuit having a 45 degree phase angle between the voltage and the current?
A. 0.866
B. 1.0
C. 0.5
D. 0.707

Back 77

D. 0.707

Front 78

What does the power factor equal in an R-L circuit having a 30 degree phase angle between the voltage and the current?
A. 1.73
B. 0.866
C. 0.5
D. 0.577

Back 78

B. 0.866

Front 79

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the supply voltage?
A. An exponential rate of one.
B. One time constant.
C. One exponential period.
D. A time factor of one.

Back 79

B. One time constant.

Front 80

What is the meaning of the term "time constant of an RC circuit"? The time required to charge the capacitor in the circuit to:
A. 23.7% of the supply voltage
B. 36.8% of the supply voltage
C. 57.3% of the supply voltage
D. 63.2% of the supply voltage

Back 80

D. 63.2% of the supply voltage

Front 81

What is the term for the time required for the current in an RL circuit to build up to 63.2% of the maximum value?
A. One time constant
B. An exponential period of one
C. A time factor of one
D. One exponential rate

Back 81

A. One time constant

Front 82

What is the meaning of the term "time constant of an RL circuit"? The time required for the:
A. Current in the circuit to build up to 36.8% of the maximum value.
B. Voltage in the circuit to build up to 63.2% of the maximum value.
C. Current in the circuit to build up to 63.2% of the maximum value.
D. Voltage in the circuit to build up to 36.8% of the maximum value.

Back 82

C. Current in the circuit to build up to 63.2% of the maximum value.

Front 83

After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage?
A. 36.8%
B. 63.2%
C. 86.5%
D. 95%

Back 83

C. 86.5%

Front 84

After two time constants, the capacitor in an RC circuit is discharged to what percentage of the starting voltage?
A. 86.5%
B. 13.5%
C. 63.2%
D. 36.8%

Back 84

B. 13.5%

Front 85

What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in parallel?
A. 22 seconds
B. 44 seconds
C. 440 seconds
D. 220 seconds

Back 85

D. 220 seconds

Front 86

What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in series?
A. 470 seconds
B. 47 seconds
C. 4.7 seconds
D. 0.47 seconds

Back 86

B. 47 seconds

Front 87

What is the time constant of a circuit having a 100-microfarad capacitor and a 470-kilohm resistor in series?
A. 4700 seconds
B. 470 seconds
C. 47 seconds
D. 0.47 seconds

Back 87

C. 47 seconds

Front 88

What is the time constant of a circuit having a 220-microfarad capacitor and a 1-megohm resistor in parallel?
A. 220 seconds
B. 22 seconds
C. 2.2 seconds
D. 0.22 seconds

Back 88

A. 220 seconds

Front 89

What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in parallel?
A. 470 seconds
B. 47 seconds
C. 4.7 seconds
D. 0.47 seconds

Back 89

B. 47 seconds

Front 90

What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in series?
A. 220 seconds
B. 55 seconds
C. 110 seconds
D. 440 seconds

Back 90

A. 220 seconds

Front 91

What is the impedance of a network composed of a 0.1 micro henry inductor in series with a 20-ohm resistor, at 30 MHz? Specify your answer in rectangular coordinates.
A. 20-j19
B. 19+j20
C. 20+j19
D. 19-j20

Back 91

C. 20+j19

Front 92

In rectangular coordinates, what is the impedance of a network composed of a 0.1-microhenry inductor in series with a 30-ohm resistor, at 5 Mhz?
A. 30-j3
B. 3+j30
C. 3-j30
D. 30+j3

Back 92

D. 30+j3

Front 93

In rectangular coordinates, what is the impedance of a network composed of a 10-microhenry inductor in series with a 40-ohm resistor, at 500 Mhz?
A. 40+j31400
B. 40-j31400
C. 31400+j40
D. 31400-j40

Back 93

A. 40+j31400

Front 94

In rectangular coordinates, what is the impedance of a network composed of a 1-millihenry inductor in series with a 200-ohm resistor, at 30 khz?
A. 200-j188
B. 200+j188
C. 188+j200
D. 188-j200

Back 94

B. 200+j188

Front 95

In rectangular coordinates, what is the impedance of a network composed of a 0.01-microfarad capacitor in parallel with a 300-ohm resistor, at 50 khz?
A. 150-j159
B. 150+j159
C. 159-j150
D. 159+j150

Back 95

C. 159-j150

Front 96

In rectangular coordinates, what is the impedance of a network composed of a 0.001-microfarad capacitor in series with a 400-ohm resistor, at 500 khz?
A. 318-j400
B. 400+j318
C. 318+j400
D. 400-j318

Back 96

D. 400-j318

Front 97

What is the impedance of a network composed of a 100-picofarad capacitor in parallel with a 4000-ohm resistor, at 500 KHz? Specify your answer in polar coordinates.
A. 2490 ohms /51.5 degrees
B. 4000 ohms /38.5 degrees
C. 5112 ohms /-38.5 degrees
D. 2490 ohms /-51.5 degrees

Back 97

D. 2490 ohms /-51.5 degrees

Front 98

In polar coordinates, what is the impedance of a network composed of a 100-ohm-reactance inductor in series with a 100-ohm resistor?
A. 121 ohms /35 degrees
B. 141 ohms /45 degrees
C. 161 ohms /55 degrees
D. 181 ohms /65 degrees

Back 98

B. 141 ohms /45 degrees

Front 99

In polar coordinates, what is the impedance of a network composed of a 400-ohm-reactance capacitor in series with a 300-ohm resistor?
A. 240 ohms /36.9 degrees
B. 240 ohms /-36.9 degrees
C. 500 ohms /-53.1 degrees
D. 500 ohms /53.1 degrees

Back 99

C. 500 ohms /-53.1 degrees

Front 100

In polar coordinates, what is the impedance of a network composed of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor,and a 400-ohm resistor, all connected in series?
A. 500 ohms /37 degrees
B. 400 ohms /27 degrees
C. 300 ohms /17 degrees
D. 200 ohms /10 degrees

Back 100

A. 500 ohms /37 degrees

Front 101

In polar coordinates, what is the impedance of a network composed of a 400-ohm-reactance inductor in parallel with a 300-ohm resistor?
A. 240 ohms /-36.9 degrees
B. 240 ohms /36.9 degrees
C. 500 ohms /53.1 degrees
D. 500 ohms /-53.1 degrees

Back 101

B. 240 ohms /36.9 degrees

Front 102

Using the polar coordinate system, what visual representation would you get of a voltage in a sinewave circuit?
A. To show the reactance which is present.
B. To graphically represent the AC and DC component.
C. To display the data on an XY chart.
D. The plot shows the magnitude and phase angle.

Back 102

D. The plot shows the magnitude and phase angle.

Front 103

What is the magnitude of the impedance of a series AC circuit having a resistance of 6 ohms, and inductive reactance of 17 ohms, and zero capacitive reactance?
A. 6.6 ohms
B. 11 ohms
C. 18 ohms
D. 23 ohms

Back 103

C. 18 ohms

Front 104

A 1-watt, 10-volt Zener diode with the following characteristics: I(min) = 5mA; I(max) = 95 mA; and Z = 8 ohms, is to be used as part of a voltage regulator in a 20-V power supply. Approximately what size current-limiting resistor would be used to set its bias to the midpoint of its operating range?
A. 100 ohms
B. 200 ohms
C. 1kilohms
D. 2 kilohms

Back 104

B. 200 ohms

Front 105

Given a power supply with a no load voltage of 12 volts and a full load voltage of 10 volts, what is the percentage of voltage regulation?
A. 17%
B. 80%
C. 20%
D. 83%

Back 105

C. 20%

Front 106

What turns ratio does a transformer need in order to match a source impedance of 500 ohms to a load of 10 ohms?
A. 7.1 to 1
B. 14.2 to 1
C. 50 to 1
D. None of these

Back 106

A. 7.1 to 1

Front 107

Given a power supply with a full load voltage of 200 volts and a regulation of 25%, what is the no load voltage?
A. 150 volts.
B. 160 volts.
C. 240 volts.
D. 250 volts.

Back 107

D. 250 volts.

Front 108

What is the conductance (G) of a circuit if 6 amperes of current flows when 12 volts DC is applied?
A. 0.25 Siemens (mhos).
B. 0.50 Siemens (mhos).
C. 1.00 Siemens (mhos).
D. 1.25 Siemens (mhos).

Back 108

B. 0.50 Siemens (mhos).

Front 109

What happens to the conductivity of photoconductive material when light shines on it?
A. It increases.
B. It decreases.
C. It stays the same.
D. It becomes temperature dependent.

Back 109

A. It increases.

Front 110

What is the photoconductive effect?
A. The conversion of photon energy to electromotive energy.
B. The increased conductivity of an illuminated semiconductor junction.
C. The conversion of electromotive energy to photon energy.
D. The decreased conductivity of an illuminated semiconductor junction.

Back 110

B. The increased conductivity of an illuminated semiconductor junction.

Front 111

What does the photoconductive effect in crystalline solids produce a noticeable change in?
A. The capacitance of the solid.
B. The inductance of the solid.
C. The specific gravity of the solid.
D. The resistance of the solid.

Back 111

D. The resistance of the solid.

Front 112

What is the description of an optoisolator?
A. An LED and a photosensitive device.
B. A P-N junction that develops an excess positive charge when exposed to light.
C. An LED and a capacitor.
D. An LED and a lithium battery cell.

Back 112

A. An LED and a photosensitive device.

Front 113

What happens to the conductivity of a photosensitive semiconductor junction when it is illuminated?
A. The junction resistance is unchanged.
B. The junction resistance decreases.
C. The junction resistance becomes temperature dependent.
D. The junction resistance increases.

Back 113

B. The junction resistance decreases.

Front 114

What is the description of an optocoupler?
A. A resistor and a capacitor.
B. Two light sources modulated onto a mirrored surface.
C. An LED and a photosensitive device.
D. An amplitude modulated beam encoder.

Back 114

C. An LED and a photosensitive device.

Front 115

What factors determine the capacitance of a capacitor?
A. Voltage on the plates and distance between the plates.
B. Voltage on the plates and the dielectric constant of the material between the plates.
C. Amount of charge on the plates and the dielectric constant of the material between the plates.
D. Distance between the plates and the dielectric constant of the material between the plates.

Back 115

D. Distance between the plates and the dielectric constant of the material between the plates.

Front 116

In Figure 3C4, if a small variable capacitor were installed in place of the dashed line, it would?


A. Increase gain.
B. Increase parasitic oscillations.
C. Decrease parasitic oscillations.
D. Decrease crosstalk.

Back 116

C. Decrease parasitic oscillations.

Front 117

In Figure 3C4, which component (labeled 1 through 4) is used to provide a signal ground?


A. 1
B. 2
C. 3
D. 4

Back 117

B. 2

Front 118

In Figure 3C5, which capacitor (labeled 1 through 4) is being used as a bypass capacitor?


A. 1
B. 2
C. 3
D. 4

Back 118

C. 3

Front 119

In Figure 3C5, the 1 F capacitor is connected to a potentiometer that is used to:
A. Increase gain.
B. Neutralize amplifier.
C. Couple.
D. Adjust tone.

Back 119

D. Adjust tone.

Front 120

What is the purpose of a coupling capacitor?
A. It blocks direct current and passes alternating current.
B. It blocks alternating current and passes direct current.
C. It increases the resonant frequency of the circuit.
D. It decreases the resonant frequency of the circuit.

Back 120

A. It blocks direct current and passes alternating current.

Front 121

A capacitor is sometimes placed in series with the primary of a power transformer to:
A. Improve the power factor.
B. Improve output voltage regulation.
C. Rectify the primary windings.
D. None of these.

Back 121

A. Improve the power factor.

Front 122

A transformer used to step up its input voltage must have:
A. More turns of wire on its primary than on its secondary.
B. More turns of wire on its secondary than on its primary.
C. Equal number of primary and secondary turns of wire.
D. None of the above statements are correct.

Back 122

B. More turns of wire on its secondary than on its primary.

Front 123

A transformer primary of 2250 turns connected to 120 VAC will develop what voltage across a 500-turn secondary?
A. 26.7 volts.
B. 2300 volts.
C. 1500 volts.
D. 5.9 volts.

Back 123

A. 26.7 volts.

Front 124

What is the ratio of the output frequency to the input frequency of a single-phase full-wave rectifier?
A. 1:1
B. 1:2
C. 2:1
D. None of these.

Back 124

C. 2:1

Front 125

A power transformer has a single primary winding and three secondary windings producing 5.0 volts, 12.6 volts, and 150 volts. Assuming similar wire sizes, which of the three secondary windings will have the highest measured DC resistance?
A. The 12.6 volt winding.
B. The 150 volt winding.
C. The 5.0 volt winding.
D. All will have equal resistance values.

Back 125

B. The 150 volt winding.

Front 126

A power transformer has a primary winding of 200 turns of #24 wire and a secondary winding consisting of 500 turns of the same size wire. When 20 volts are applied to the primary winding, the expected secondary voltage will be:
A. 500 volts
B. 25 volts
C. 10 volts
D. 50 volts

Back 126

D. 50 volts

Front 127

In a linear electronic voltage regulator:
A. The output is a ramp voltage.
B. The pass transistor switches from the "off" state to the "on" state.
C. The control device is switched on or off, with the duty cycle proportional to the line or load conditions.
D. The conduction of a control element is varied in direct proportion to the line voltage or load current.

Back 127

D. The conduction of a control element is varied in direct proportion to the line voltage or load current.

Front 128

A switching electronic voltage regulator:
A. Varies the conduction of a control element in direct proportion to the line voltage or load current.
B. Provides more than one output voltage.
C. Switches the control device on or off, with the duty cycle proportional to the line or load conditions.
D. Gives a ramp voltage at its output.

Back 128

C. Switches the control device on or off, with the duty cycle proportional to the line or load conditions.

Front 129

What device is usually used as a stable reference voltage in a linear voltage regulator?
A. Zener Diode
B. Tunnel Diode
C. SCR
D. Varactor Diode

Back 129

A. Zener Diode

Front 130

In a regulated power supply, what type of component will most likely be used to establish a reference voltage?
A. Tunnel Diode
B. Battery
C. Pass Transistor
D. Zener Diode

Back 130

D. Zener Diode

Front 131

A three-terminal regulator:
A. Supplies three voltages with a variable current.
B. Supplies three voltages with a constant current.
C. Contains a voltage reference, error amplifier, sensing resistors and transistors, and a pass element.
D. Contains three error amplifiers and sensing transistors.

Back 131

C. Contains a voltage reference, error amplifier, sensing resistors and transistors, and a pass element.

Front 132

What is the range of voltage ratings available in Zener diodes?
A. 1.2 volts to 7 volts.
B. 2.4 volts to 200 volts and above.
C. 3 volts to 2000 volts.
D. 1.2 volts to 5.6 volts.

Back 132

B. 2.4 volts to 200 volts and above.

Front 133

How might two similar SCRs be connected to safely distribute the power load of a circuit?
A. In series.
B. In parallel, same polarity.
C. In parallel, reverse polarity.
D. In a combination series and parallel configuration.

Back 133

C. In parallel, reverse polarity.

Front 134

What are the three terminals of an SCR?
A. Anode, cathode, and gate.
B. Gate, source, and sink.
C. Base, collector, and emitter.
D. Gate, base 1, and base 2.

Back 134

A. Anode, cathode, and gate.

Front 135

Which of the following devices acts as two SCRs connected back to back, but facing in opposite directions and sharing a common gate?
A. JFET
B. Dual-gate MOSFET
C. DIAC
D. TRIAC

Back 135

D. TRIAC

Front 136

What is the transistor called that is fabricated as two complementary SCRs in parallel with a common gate terminal?
A. TRIAC
B. Bilateral SCR
C. Unijunction transistor
D. Field effect transistor

Back 136

A. TRIAC

Front 137

What are the three terminals of a TRIAC?
A. Emitter, base 1, and base 2.
B. Base, emitter, and collector.
C. Gate, source, and sink.
D. Gate, anode 1, and anode 2.

Back 137

D. Gate, anode 1, and anode 2.

Front 138

What circuit might contain a SCR?
A. Filament circuit of a tube radio receiver.
B. A light-dimming circuit.
C. Shunt across a transformer primary.
D. Bypass capacitor circuit to ground.

Back 138

B. A light-dimming circuit.

Front 139

What is one common use for PIN diodes?
A. Constant current source.
B. RF switch.
C. Constant voltage source.
D. RF rectifier.

Back 139

B. RF switch.

Front 140

What is a common use of a hot-carrier diode?
A. Balanced inputs in SSB generation.
B. Variable capacitance in an automatic frequency control circuit.
C. Constant voltage reference in a power supply.
D. VHF and UHF mixers and detectors.

Back 140

D. VHF and UHF mixers and detectors.

Front 141

Structurally, what are the two main categories of semiconductor diodes?
A. Junction and point contact.
B. Electrolytic and junction.
C. Electrolytic and point contact.
D. Vacuum and point contact.

Back 141

A. Junction and point contact.

Front 142

What type of diode is capable of both amplification and oscillation?
A. Zener diodes.
B. Point contact diodes.
C. Tunnel diodes.
D. Junction diodes.

Back 142

C. Tunnel diodes.

Front 143

What type of semiconductor diode varies its internal capacitance as the voltage applied to its terminals varies?
A. Tunnel diode.
B. Varactor diode.
C. Silicon-controlled rectifier.
D. Zener diode.

Back 143

B. Varactor diode.

Front 144

What is the principal characteristic of a tunnel diode?
A. High forward resistance.
B. Very high PIV(peak inverse voltage).
C. Negative resistance region.
D. High forward current rating.

Back 144

C. Negative resistance region.

Front 145

What is the meaning of the term "alpha" with regard to bipolar transistors? The change of:
A. Collector current with respect to base current.
B. Base current with respect to collector current.
C. Collector current with respect to gate current.
D. Collector current with respect to emitter current.

Back 145

D. Collector current with respect to emitter current.

Front 146

What are the three terminals of a bipolar transistor?
A. Cathode, plate and grid.
B. Base, collector and emitter.
C. Gate, source and sink.
D. Input, output and ground.

Back 146

B. Base, collector and emitter.

Front 147

What is the meaning of the term "beta" with regard to bipolar transistors? The change of:
A. Base current with respect to emitter current.
B. Collector current with respect to emitter current.
C. Collector current with respect to base current.
D. Base current with respect to gate current.

Back 147

C. Collector current with respect to base current.

Front 148

What are the elements of a unijunction transistor?
A. Base 1, base 2, and emitter.
B. Gate, cathode, and anode.
C. Gate, base 1, and base 2.
D. Gate, source, and sink.

Back 148

A. Base 1, base 2 and emitter.

Front 149

The beta cutoff frequency of a bipolar transistor is the frequency at which:
A. Base current gain has increased to 0.707 of maximum.
B. Emitter current gain has decreased to 0.707 of maximum.
C. Collector current gain has decreased to 0.707.
D. Gate current gain has decreased to 0.707.

Back 149

B. Emitter current gain has decreased to 0.707 of maximum.

Front 150

What does it mean for a transistor to be fully saturated?
A. The collector current is at its maximum value.
B. The collector current is at its minimum value.
C. The transistor's Alpha is at its maximum value.
D. The transistor's Beta is at its maximum value.

Back 150

A. The collector current is at its maximum value.

Front 151

A common base amplifier has:
A. More current gain than common emitter or common collector.
B. More voltage gain than common emitter or common collector.
C. More power gain than common emitter or common collector.

Back 151

B. More voltage gain than common emitter or common collector.

Front 152

What does it mean for a transistor to be cut off?
A. There is no base current.
B. The transistor is at its Class A operating point.
C. There is no current between emitter and collector.
D. There is maximum current between emitter and collector.

Back 152

C. There is no current between emitter and collector.

Front 153

An emitter-follower amplifier has:
A. More voltage gain than common emitter or common base.
B. More power gain than common emitter or common base.
C. Lowest input impedance of the three amplifier configurations.
D. More current gain than common emitter or common base.

Back 153

D. More current gain than common emitter or common base.

Front 154

What conditions exists when a transistor is operating in saturation?
A. The base-emitter junction and collector-base junction are both forward biased.
B. The base-emitter junction and collector-base junction are both reverse biased.
C. The base-emitter junction is reverse biased and the collector-base junction is forward biased.
D. The base-emitter junction is forward biased and the collector-base junction is reverse biased.

Back 154

A. The base-emitter junction and collector-base junction are both forward biased.

Front 155

For current to flow in an NPN silicon transistor's emitter-collector junction, the base must be:
A. At least 0.4 volts positive with respect to the emitter.
B. At a negative voltage with respect to the emitter.
C. At least 0.7 volts positive with respect to the emitter.
D. At least 0.7 volts negative with respect to the emitter.

Back 155

C. At least 0.7 volts positive with respect to the emitter.

Front 156

When an NPN transistor is operating as a Class A amplifier, the base-emitter junction:
A. And collector-base junction are both forward biased.
B. And collector-base junction are both reverse biased.
C. Is reverse biased and the collector-base junction is forward biased.
D. Is forward biased and the collector-base junction is reverse biased.

Back 156

D. Is forward biased and the collector-base junction is reverse biased.

Front 157

What type of bias is required for an LED to produce luminescence?
A. reverse bias.
B. Forward bias.
C. Logic 0 (Lo) bias.
D. Logic 1 (Hi) bias.

Back 157

B. Forward bias.

Front 158

What determines the visible color radiated by an LED junction?
A. The color of a lens in an eyepiece.
B. The amount of voltage across the device.
C. The amount of current through the device.
D. The materials used to construct the device.

Back 158

D. The materials used to construct the device.

Front 159

What is the approximate operating current of a light-emitting diode?
A. 20 mA.
B. 5 mA.
C. 10 mA.
D. 400 mA.

Back 159

A. 20 mA.

Front 160

What would be the maximum current to safely illuminate a LED?
A. 1 amp.
B. 1 microamp.
C. 500 milliamps.
D. 20 mA.

Back 160

D. 20 mA.

Front 161

An LED facing a photodiode in a light-tight enclosure is commonly known as a/an:
A. Optoisolator.
B. Seven segment LED.
C. Optointerrupter.
D. Infra-red (IR) detector.

Back 161

A. Optoisolator.

Front 162

What circuit component must be connected in series to protect an LED?
A. Bypass capacitor to ground.
B. Electrolytic capacitor.
C. Series resistor.
D. Shunt coil in series.

Back 162

C. Series resistor.

Front 163

What describes a diode junction that is forward biased?
A. It is a high impedance.
B. It conducts very little current.
C. It is a low impedance.
D. It is an open circuit.

Back 163

C. It is a low impedance.

Front 164

Why are special precautions necessary in handling FET and CMOS devices?
A. They have fragile leads that may break off.
B. They are susceptible to damage from static charges.
C. They have micro-welded semiconductor junctions that are susceptible to breakage.
D. They are light sensitive.

Back 164

B. They are susceptible to damage from static charges.

Front 165

What do the initials CMOS stand for?
A. Common mode oscillating system.
B. Complementary mica-oxide silicon.
C. Complementary metal-oxide semiconductor.
D. Complementary metal-oxide substrate.

Back 165

C. Complementary metal-oxide semiconductor.

Front 166

What is the piezoelectric effect?
A. Mechanical bibration of a crystal by the application of a voltage.
B. Mechanical deformation of a crystal byt he application of a magnetic field.
C. The generation of electrical energy by the application of light.
D. Reversed conduction states when a P-N junction is exposed to light.

Back 166

A. Mechanical vibration of a crystal by the application of a voltage.

Front 167

An electrical relay is a :
A. Current limiting device.
B. Device used for supplying 3 or more voltages to a circuit.
C. Component used mainly with HF audio amplifiers.
D. Remotely controlled switching device.

Back 167

D. Remotely controlled switching device.

Front 168

In which oscillator circuit would you find a quartz crystal?
A. Hartley.
B. Pierce.
C. Colpitts.
D. All of the above.

Back 168

B. Pierce.

Front 169

What is the approximate magnitude of the impedance of a parallel R-L-C circuit at resonance?
A. Approximately equal to the circuit resistance.
B. Approximately equal to X.
C. Low, as compared to the circuit resistance.
D. Approximately equal to X.

Back 169

A. Approximately equal to the circuit resistance.

Front 170

What is the approximate magnitude of the impedance of a series R-L-C circuit at resonance?
A. High, as compared to the circuit resistance.
B. Approximately equal to the circuit resistance.
C. Approximately equal to X.
D. Approximately equal to X.

Back 170

B. Approximately equal to the circuit resistance.

Front 171

How could voltage be greater across reactances in series than the applied voltage?
A. Resistance.
B. Conductance.
C. Capacitance.
D. Resonance.

Back 171

D. Resonance

Front 172

What is the characteristic of the current flow in a series R-L-C circuit at resonance?
A. Maximum.
B. Minimum.
C. DC.
D. Zero.

Back 172

A. Maximum

Front 173

What is the characteristic of the current flow within the parallel elements in a parallel R-L-C circuit at resonance?
A. Minimum.
B. Maximum.
C. DC.
D. Zero.

Back 173

B. Maximum

Front 174

What is the relationship between current through a resonant circuit and the voltage across the circuit?
A. The current and voltage are 180 degrees out of phase.
B. The current leads the voltage by 90 degrees.
C. The voltage and current are in phase.
D. The voltage leads the current by 90 degrees.

Back 174

C. The voltage and current are in phase.

Front 175

What is the main advantage of using an op-amp audio filter over a passive LC audio filter?
A. Op-amps are largely immune to vibration and temperature change.
B. Most LC filter manufacturers have retooled to make op-amp filters.
C. Op-amps are readily available in a wide variety of operational voltages and frequency ranges.
D. Op-amps exhibit gain rather than insertion loss.

Back 175

D. Op-amps exhibit gain rather than insertion loss.

Front 176

What are the characteristics of an inverting operational amplifier (op-amp) circuit?
A. It has input and output signals in phase.
B. Input and output signals are 90 degrees out of phase.
C. It has input and output signals 180 degrees out of phase.
D. Input impedance is low while the output impedance is high.

Back 176

C. It has input and output signals 180 degrees out of phase.

Front 177

Gain of a closed-loop op-amp circuit is determined by?
A. The maximum operating frequency divided by the square root of the load impedance.
B. The op-amp's external feedback network.
C. Supply voltage and slew rate.
D. The op-amp's internal feedback network.

Back 177

B. The op-amp's external feedback network.

Front 178

Where is the external feedback network connected to control the gain of a closed-loop op-amp circuit?
A. Between the differential inputs.
B. From output to the non-inverting input.
C. From output to the inverting input.
D. Between the output and the differential inputs.

Back 178

C. From output to the inverting input.

Front 179

Which of the following op-amp circuits is operated open-loop?
A. Non-inverting amp.
B. Inverting amp.
C. Active filter.
D. Comparator.

Back 179

D. Comparator.

Front 180

In the op-amp oscillator circuit shown in Figure 3D6, what would be the most noticeable effect if the capacitance of C were suddenly doubled?
A. Frequency would be lower.
B. Frequency would be higher.
C. There would be no change. The inputs are reversed, therefore the circuit cannot function.
D. None of the above.

Back 180

A. Frequency would be lower.

Front 181

What frequency synthesizer circuit uses a phase comparator, look-up table, digital-to-analog converter, and a low-pass antialias filter?
A. A direct digital synthesizer.
B. Phase-locked-loop synthesizer.
C. A diode-switching matrix synthesizer.
D. A hybrid synthesizer.

Back 181

A. A direct digital synthesizer.

Front 182

A circuit that compares the output of a voltage-controlled oscillator (VCO) to a frequency standard and produces an error voltage that is then used to adjust the capacitance of a varactor diode used to control frequency in that same VCO is called what?
A. Doubly balanced mixer.
B. Phase-locked loop.
C. Differential voltage amplifier.
D. Variable frequency oscillator.

Back 182

B. Phase-lokced loop.

Front 183

RF input to a mixer is 200 MHz and the local oscillator frequency is 150 MHz. What output would you expect to see at the iF output prior to any filtering?
A. 50, 150, 200 and 350 MHz.
B. 50 MHz
C. 350 MHz.
D. 50 and 350 MHz.

Back 183

A. 50, 150, 200 and 350 MHz.

Front 184

What spectral impurity components might be generated by a phase-locked-loop synthesizer?
A. Spurs at discrete frequencies.
B. Random spurs which gradually drift up in frequency.
C. Broadband noise.
D. Digital conversion noise.

Back 184

C. Broadband noise.

Front 185

In a direct digital synthesizer, what are the unwanted components on its output?
A. Broadband noise.
B. Spurs at discrete frequencies.
C. Digital conversion noise.
D. Nyquist limit noise pulses.

Back 185

B. Spurs at discrete frequencies.

Front 186

What is the definition of a phase-lokced loop (PLL) circuit?
A. A servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator.
B. A circuit also known as a monostable multivibrator.
C. A circuit consisting of a precision push-pull amplifier with a differential input.
D. A servo loop consisting of a phase detector, a low-pass filter and voltage-controlled oscillator.

Back 186

D. A servo loop consisting of a phase detector, a low-pass filter and voltage-controlled oscillator.

Front 187

Given the combined DC input voltages, what would the output voltage be in the circuit shown in Figure 3D7?
A. 150 mV
B. 5.5 V
C. -15 mv
D. -5.5 V

Back 187

D. -5.5 V

Front 188

Which lamps would be lit in the circuit shown in Figure 3D8?
A. 2, 3, 4, 5 and 6.
B. 5, 6, 8 and 9.
C. 2, 3, 4, 7 and 8.
D. 1, 3, 5, 7 and 8.

Back 188

C. 2, 3, 4, 7 and 8.

Front 189

What will occur if an amplifier input signal coupling capacitor fails open?
A. No amplification will occur, with DC within the circuit measuring normal.
B. Improper biasing will occur within the amplifier stage.
C. Oscillation and thermal runaway may occur.
D. An AC hum will appear on the circuit output.

Back 189

A. No amplification will occur, with DC within the circuit measuring normal.

Front 190

In Figure 3D9, determine if there is a problem with this regulated power supply and identify the problem.
A. R1 value is too low which would cause excessive base current and instantly destroy TR 1.
B. D1 and D2 are reversed. The power supply simply would not function.
C. TR1 is shown as an NPN and must be changed to a PNP.
D. There is no problem with the circuit.

Back 190

D. There is no problem with the circuit.

Front 191

In Figure 3D10 with a square wave input what would be the output? Page 121
A. 1
B. 2
C. 3
D. 4

Back 191

C. 3

Front 192

With a pure AC signal input to the circuit shown in Figure 3D11, what output wave form would you expect to see on an oscilloscope display?
A. 1
B. 2
C. 3
D. 4

Back 192

B. 2

Front 193

What is the voltage range considered to be valid logic low input in a TTL device operating at 5 volts?
A. 2.0 to 5.5 volts.
B. -2.0 to -5.5 volts.
C. Zero to 0.8 volts.
D. 5.2 to 34.8 volts.

Back 193

C. Zero to 0.8 volts.

Front 194

What is the voltage range considered to be a valid logic high input in a TTL device operating at 5.0 volts?
A. 2.0 to 5.5 volts.
B. 1.5 to 3.0 volts.
C. 1.0 to 1.5 volts.
D. 5.2 to 34.8 volts.

Back 194

A. 2.0 to 5.5 volts.

Front 195

What is the common power supply voltage for TTL series integrated circuits?
A. 12 volts.
B. 13.6 volts.
C. 1 volt.
D. 5 volts.

Back 195

D. 5 volts.

Front 196

TTL inputs left open develop what logic state?
A. A high-logic state.
B. A low-logic state.
C. Open inputs on a TTL device are ignored.
D. Random high- and low-logic states.

Back 196

A. A high-logic state.

Front 197

Which of the following instruments would be best for checking a TTL logic circuit?
A. VOM.
B. DMM.
C. Continuity tester.
D. Logic probe.

Back 197

D. Logic probe.

Front 198

What do the initials TTL stand for?
A. Resistor-transistor logic.
B. Transistor-transistor logic.
C. Diode-transistor logic.
D. Emitter-coupled logic.

Back 198

B. Transistor-transistor logic.

Front 199

What is a characteristic of an AND gate?
A. Produces a logic "0" at its output only if all inputs are logic "1".
B. Produces a logic "1" at its output only if all inputs are logic "1".
C. Produces a logic "1" at its output if only one input is a logic "1".
D. Produces a logic "1" at its output if all inputs are logic "0".

Back 199

B. Produces a logic "1" at its output only if all inputs are logic "1".

Front 200

What is a characteristic of a NAND gate?
A. Produces a logic "0" at its output only when all inputs are logic "0".
B. Produces a logic "1" at its output only when all inputs are logic "1".
C. Produces a logic "0" at its output if some but not all of its inputs are logic "1".
D. Produces a logic "0" at its output only when all inputs are logic "1".

Back 200

D. Produces a logic "0" at its output only when all inputs are logic "1".

Front 201

What is a characteristic of an OR gate?
A. Produces a logic "1" at its output if any input is logic "1".
B. Produces a logic "0" at its output if any input is logic '1".
C. Produces a logic "0" at its output if all inputs are logic "1".
D. Produces a logic "1" at its output if all inputs are logic "0".

Back 201

A. Produces a logic "1" at its output if any input is logic "1".

Front 202

What is a characteristic of a NOR gate?
A. Produces a logic "0" at its output only if all inputs are logic "0".
B. Produces a logic "1" at its output only if all inputs are logic "1".
C. Produces a logic "0" at its output if any or all inputs are logic "1".
D. Produces a logic "1" at its output if some but not all of its inputs are logic "1".

Back 202

C. Produces a logic "0" at its output if any or all inputs are logic "1".

Front 203

What is a characteristic of a NOT gate?
A. Does not allow data transmission when its input is high.
B. Produces a logic "0" at its output when the input is logic "1" and vice versa.
C. Allows data transmission only when its input is high.
D. Produces a logic "1" at its output when the input is logic "1" and vice versa.

Back 203

B. Produces a logic "0" at its output when the input is logic "1" and vice versa.

Front 204

Which of the following logic gates will provide an active high out when both inputs are active high?
A. NAND.
B. NOR.
C. AND
D. XOR.

Back 204

C. AND

Front 205

In a negative-logic circuit, what level is used to represent a logic 0?
A. Low level.
B. Positive-transition level.
C. Negative-transition level.
D. High level.

Back 205

D. High level.

Front 206

For the logic input levels shown in Figure 3E12, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is high, B is low and C is low.
B. A is low, B is high and C is high.
C. A is high, B is high and C is low.
D. A is low, B is high and C is low.

Back 206

B. A is low, B is high and C is high.

Front 207

For the logic input levels given in Figure 3E13, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is low, B is low and C is high.
B. A is low, B is high and C is low.
C. A is high, B is high and C is high.
D. A is high, B is low and C is low.

Back 207

C. A is high, B is high and C is high.

Front 208

In a positive-logic circuit, what level is used to represent a logic 1?
A. High level
B. Low level
C. Positive-transition level
D. Negative-transion level

Back 208

A. High level

Front 209

Given the input levels shown in Figure 3E14 and assuming positive logic devices, what would the output be?
A. A is low, B is high and Cis high.
B. A is high, B is high and C is low.
C. A is low, B is low and C is high.
D. None of the above are correct.

Back 209

A. A is low, B is high and C is high.

Front 210

What is a truth table?
A. A list of input combinations and their corresponding outputs that characterizes a digital device's function.
B. A table of logic symbols that indicate the high logic states of an op-amp.
C. A diagram showing logic states when the digital device's output is true.
D. A table of logic symbols that indicates the low logic states of an op-amp.

Back 210

A. A list of input combinations and their corresponding outputs that characterizes a digital device's function.

Front 211

A flip-flop circuit is a binary logic element with how many stable states?
A. 1
B. 2
C. 4
D. 8

Back 211

B. 2

Front 212

What is a flip-flop circuit? A binary sequential logic element with ___ stable states.
A. 1
B. 4
C. 2
D. 8

Back 212

C. 2

Front 213

How many flip-flops are required to divide a signal frequency by 4?
A. 1
B. 4
C. 8
D. 2

Back 213

D. 2

Front 214

How many bits of information can be stored in a single flip-flop circuit?
A. 1
B. 2
C. 3
D. 4

Back 214

A. 1

Front 215

How many R-S flip-flops would be required to constrict an 8 bit storage register?
A. 2
B. 4
C. 8
D. 16

Back 215

C. 8

Front 216

An R-S flip-flop is capable of doing all of the following except:
A. Accept data input into R-S inputs with CLK initiated.
B. Accept data input into PRE and CLR inputs without CLK being initiated.
C. Refuse to accept synchronous data if asynchronous data is being input at same time.
D. Operate in toggle mode with R-S inputs held constant and CLK initiated.

Back 216

D. Operate in toggle mode with R-S inputs held constant and CLK initiated.

Front 217

The frequency of an AC signal can be divided electronically by what type of digital circuit?
A. Free-running multivibrator.
B. Bistable multivibrator.
C. OR gate.
D. Astable multivibrator.

Back 217

B. Bistable multivibrator.

Front 218

What is an astable multivibrator?
A. A circuit that alternates between two stable states.
B. A circuit that alternates between a stable state and an unstable state.
C. A circuit set to block either a 0 pulse or a 1 pulse and pass the other.
D. A circuit that alternates between two unstable states.

Back 218

D. A circuit that alternates between two unstable states.

Front 219

What is a monostable multivibrator?
A. A circuit that can be switched momentarily to the opposite binary state and then returns after a set time to its original state.
B. A "clock" circuit that produces a continuous square wave oscillating between 1 and 0.
C. A circuit designed to store one bit of data in either the 0 or the 1 configuration.
D. a circuit that maintains a constant output voltage, regardless of variations in the input voltage.

Back 219

A. A circuit that can be switched momentarily to the opposite binary state and then returns after a set time to its original state.

Front 220

What is a bistable multivibrator circuit commonly named?
A. AND gate.
B. OR gate.
C. Clock.
D. Flip-flop.

Back 220

D. Flip-flop.

Front 221

What is a bistable multivibrator circuit?
A. Flip-flop.
B. AND gate.
C. OR gate.
D. Clock.

Back 221

A. Flip-flop

Front 222

What wave form would appear on the voltage outputs at the collectors of an astable, multivibrator, common-emitter stage?
A. Sine wave.
B. Sawtooth wave.
C. Square wave.
D. Half-wave pulses.

Back 222

C. Square wave.

Front 223

What is the name of the semiconductor memory IC whose digital data can be written or read, and whose memory word address can be accessed randomly?
A. ROM- Read-Only Memory.
B. PROM - Programmable Read-Only Memory.
C. RAM -Random-Access Memory.
D. EPROM-Electrically Programmable Read-Only Memory.

Back 223

C. RAM - Random-Access Memory.

Front 224

What is the name of the semiconductor IC that has a fixed pattern of digital data stored in its memory matrix?
A. RAM - Random-Access Memory.
B. ROM - Read-Only Memory.
C. Register.
D. Latch.

Back 224

B. ROM - Read-Only Memory.

Front 225

What does the term "IO" mean within a microprocessor system?
A. Integrated oscillator.
B. Integer operation.
C. Input-output.
D. Internal operation.

Back 225

C. Input-output.

Front 226

What is the name for a microprocessor's sequence of commands and instructions?
A. Program.
B. Sequence.
C. Data string.
D. Data execution.

Back 226

A. Program.

Front 227

How many individual memory cells would be contained in a memory IC that has 4 data bus input/output pins and 4 address pins for connection to the address bus?
A. 8
B. 16
C. 32
D. 64

Back 227

D. 64

Front 228

What is the name of the random-accessed semiconductor memory IC that must be refreshed periodically to maintain reliable data storage in its memory matrix?
A. ROM - Read-Only Memory.
B. DRAM - Dynamic Random-Access Memory.
C. PROM - Programmable Read-Only Memory.
D. PRAM - Programmable Random - Access Memory.

Back 228

B. DRAM - Dynamic Random- Access Memory.

Front 229

In a microprocessor-controlled two-way radio, a "watchdog" timer:
A. Verifies that the microprocessor is executing the program.
B. Assures that the transmission is exactly on frequency.
C. Prevents the transmitter from exceeding allowed power out.
D. Connects to the system RADAR presentation.

Back 229

A. Verifies that the microprocessor is executing the program.

Front 230

What does the term "DAC" refer to in a microprocessor circuit?
A. Dynamic access controller.
B. Digital to analog converter.
C. Digital access counter.
D. Dial analog control.

Back 230

B. Digital to analog converter.

Front 231

Which of the following is not part of a MCU processor?
A. RAM
B. ROM
C. I/O
D. Voltage Regulator

Back 231

D. Voltage Regulator

Front 232

What portion of a microprocessor circuit is the pulse generator?
A. Clock
B. RAM
C. ROM
D. PLL

Back 232

A. Clock

Front 233

In a microprocessor, what is the meaning of the term "ALU"?
A. Automatic lock/unlock.
B. Arithmetical logic unit.
C. Auto latch undo.
D. Answer local unit.

Back 233

B. Arithmetical logic unit.

Front 234

What circuit interconnects the microprocessor with the memory and input/output system?
A. Control logic bus.
B. PLL line.
C. Data bus line.
D. Directional coupler.

Back 234

C. Data bus line.

Front 235

What is the purpose of a prescaler circuit?
A. Converts the output of a JK flip-flop to that of an RS flip-flop.
B. Multiplies an HF signal so a low-frequency counter can display the operating frequency.
C. Prevents oscillation in a low frequency counter circuit.
D. Divides an HF signal so that a low-frequency counter can display the operating frequency.

Back 235

D. Divides an HF signal so that a low-frequency counter can display the operating frequency.

Front 236

What does the term "BCD" mean?
A. Binaural coded digit.
B. Bit count decimal.
C. Binary coded decimal.
D. Broad course digit.

Back 236

C. Binary coded decimal.

Front 237

What is the function of a decade counter digital IC?
A. Decode a decimal number for display on a seven-segment LED display.
B. Produce one output pulse for every ten input pulses.
C. Produce ten output pulses for every input pulse.
D. Add two decimal numbers.

Back 237

B. Produce one output pulse for every ten input pulses.

Front 238

What integrated circuit device converts digital signals to digital signals?
A. DAC
B. DCC
C. ADC
D. CDC

Back 238

C. ADC

Front 239

What integrated circuit device converts digital signals to analog signals?
A. ADC
B. DCC
C. CDC
D. DAC

Back 239

D. DAC

Front 240

In binary numbers, how would you note the quantity TWO?
A. 0010
B. 0002
C. 2000
D. 0020

Back 240

A. 0010

Front 241

What is the limiting condition for sensitivity in a communications receiver?
A. The noise floor of the receiver.
B. The power supply output ripple.
C. The two-tone intermodulation distortion.
D. The input impedance to the detector.

Back 241

A. The noise floor of the receiver.

Front 242

What is the definition of the term "receiver desensitizing"?
A. A burst of noise when the squelch is set too low.
B. A reduction in receiver sensitivity because of a strong signal on a nearby frequency.
C. A burst of noise when the squelch is set too high.
D. A reduction in receiver sensitivity when the AF gain control is turned down.

Back 242

B. A reduction in receiver sensitivity because of a strong signal on a nearby frequency.

Front 243

What is the term used to refer to a reduction in receiver sensitivity caused by unwanted high-level adjacent channel signals?
A. Desensitizing.
B. Intermodulation distortion.
C. Quieting.
D. Overloading.

Back 243

A. Desensitizing.

Front 244

What is meant by the term noise figure of a communications receiver?
A. The level of noise entering the receiver from the antenna.
B. The relative strength of a received signal 3 kHz removed from the carrier frequency.
C. The level of noise generated in the front end and succeeding stages of a receiver.
D. The ability of a receiver to reject unwanted signals at frequencies close to the desired one.

Back 244

C. The level of noise generated in the front end and succeeding stages of a receiver.

Front 245

Which stage of a receiver primarily establishes its noise figure?
A. The audio stage.
B. The RF stage.
C. The IF strip.
D. The local oscillator.

Back 245

B. The RF stage.

Front 246

What is the term for the ratio between the largest tolerable receiver input signal and the minimum discernible signal?
A. Intermodulation distortion.
B. Noise floor.
C. Noise figure.
D. Dynamic range.

Back 246

D. Dynamic range.

Front 247

How can selectivity be achieved in the front-end circuitry of a communications receiver?
A. By using an audio filter.
B. By using an additional RF amplifier stage.
C. By using an additional IF amplifier stage.
D. By using a preselector.

Back 247

D. By using a preselector.

Front 248

What is the primary purpose of an RF amplifier in a receiver?
A. To provide most of the receiver gain.
B. To vary the receiver image rejection by utilizing the AGC.
C. To improve the receiver's noise figure.
D. To develop the AGC voltage.

Back 248

C. To improve the receiver's noise figure.

Front 249

How much gain should be used in the RF amplifier stage of a receiver?
A. Sufficient gain to allow weak signals to overcome noise generated in the first mixer stage.
B. As much gain as possible short of self oscillation.
C. Sufficient gain to keep weak signals below the noise of the first mixer stage.
D. It depends on the amplification factor of the first IF stage.

Back 249

A. Sufficient gain to allow weak signals to overcome noise generated in the first mixer stage.

Front 250

Too much gain in a VHF receiver front end could result in this:
A. Local signals become weaker.
B. Difficult to match receiver impedances.
C. Dramatic increase in receiver current.
D. Susceptibility of intermodulation interference from nearby transmitters.

Back 250

D. Susceptibility of intermodulation interference from nearby transmitters.

Front 251

What is the advantage of a GaAsFET preamplifier in a modern VHF radio receiver?
A. Increased selectivity and flat gain.
B. Low gain but high selectivity.
C. High gain and low noise floor.
D. High gain with high noise floor.

Back 251

C. High gain and low noise floor.

Front 252

In what stage of a VHF receiver would a low noise amplifier be most advantageous?
A. IF stage.
B. Front end RF stage.
C. Audio stage.
D. Power supply.

Back 252

B. Front end RF stage.

Front 253

Why is the Colpitts oscillator circuit commonly used in a VFO (variable frequency oscillator)?
A. It can be phase locked.
B. It can be remotely tuned.
C. It is stable.
D. It has little or no effect on the crystal's stability.

Back 253

C. It is stable.

Front 254

What is the oscillator stage called in a frequency synthesizer?
A. VCO
B. Divider.
C. Phase detector.
D. Reference standard.

Back 254

A. VCO

Front 255

What are three major oscillator circuits found in radio equipment?
A. Taft, Pierce, and negative feedback.
B. Colpitts, Hartley, and taft.
C. Taft, Hartley, and Pierce.
D. Reference standard.

Back 255

D. Colpitts, Hartley, and Pierce.

Front 256

Which type of oscillator circuit is commonly used in a VFO (variable frequency oscillator)?
A. Colpitts.
B. Pierce.
C. Hartley.
D. Negative feedback.

Back 256

A. Colpitts.

Front 257

What condition must exist for a circuit to oscillate? It must:
A. Have a gain of less than 1.
B. Be neutralized.
C. Have sufficient negative feedback.
D. Have sufficient positive feedback.

Back 257

D. Have sufficient positive feedback.

Front 258

In Figure 3F15, which block diagram symbol (labeled 1 through 4) is used to represent a local oscillator?
A. 1
B. 2
C. 3
D. 4

Back 258

B. 2

Front 259

What is the image frequency if the normal channel is 151.000 MHz, the IF is operating at 11.000 MHz, and the LO is at 140.000 MHz?
A. 131.000 MHz.
B. 129.000 MHz.
C. 162.000 MHz.
D. 150.000 MHz.

Back 259

B. 129.000 MHz.

Front 260

What is the mixing process in a radio receiver?
A. The elimination of noise in a wideband receiver by phase comparison.
B. The elimination of noise in a wideband receiver by phase differentiation.
C. Distortion caused by auroral propagation.
D. The combination of two signals to produce sum and difference frequencies.

Back 260

D. The combination of two signals to produce sum and difference frequencies.

Front 261

In what radio stage is the image frequency normally rejected?
A. RF.
B IF.
C. LO.
D. Detector.

Back 261

A. RF.

Front 262

What are the principal frequencies that appear at the output of a mixer circuit?
A. Two and four times the original frequency.
B. The sum, difference and square root of the input frequencies.
C. The original frequencies and the sum and difference frequencies.
D. 1.414 and 0.707 times the input frequency.

Back 262

C. The original frequencies and the sum and difference frequencies.

Front 263

If a receiver mixes a 13.8 MHz VFO with a 14.255 MHz receive signal to produce a 455 kHz intermediate frequency signal, what type of interference will a 13.345 MHz signal produce in the receiver?
A. Local oscillator interference.
B. An image response.
C. Mixer interference.
D. Intermediate frequency interference.

Back 263

B. An image response.

Front 264

What might occur in a receiver if excessive amounts of signal energy overdrive the mixer circuit?
A. Automatic limiting occurs.
B. Mixer blanking occurs.
C. Spurious mixer products are generated.
D. The mixer circuit becomes unstable and drifts.

Back 264

C. Spurious mixer products are generated.

Front 265

What degree of selectivity is desirable in the IF circuitry of a wideband FM phone receiver?
A. 1 kHz.
B. 2.4 kHz.
C. 4.2 kHz.
D. 15 kHz.

Back 265

D. 15 kHz.

Front 266

Which one of these filters can be used in micro-miniature electronic circuits?
A. High power transmitter cavity.
B. Receiver SAW IF filter.
C. Floppy disk controller.
D. internet DSL to telephone line filter.

Back 266

B. Receiver SAW IF filter.

Front 267

A receiver selectivity of 2.4 kHz in the IF circuitry is optimum for what type of signals?
A. CW.
B. Double-sideband AM voice.
C. SSB voice.
D. FSK RTTY.

Back 267

C. SSB voice.

Front 268

A receiver selectivity of 10 kHz in the IF circuitry is optimum for what type of signals?
A. Double-sideband AM.
B. SSB voice
C. CW.
D. FSK RTTY

Back 268

A. Double -sideband AM.

Front 269

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?
A. Output-offset overshoot.
B. Undesired signals will reach the audio stage.
C. Thermal-noise distortion.
D. Filter ringing.

Back 269

B. Undesired signals will reach the audio stage.

Front 270

How should the filter bandwidth of a receiver IF section compare with the bandwidth of a received signal?
A. Slightly greater than the received-signal bandwidth.
B. Approximately half the received-signal bandwidth.
C. Approximately two times the received-signal bandwidth.
D. Approximately four times the received-signal bandwidth.

Back 270

A. Slightly greater than the received-signal bandwidth.

Front 271

What is the primary purpose of the final IF amplifier stage in a receiver?
A. Dynamic response.
B. Gain.
C. Noise figure performance.
D. Bypass undesired signals.

Back 271

B. Gain.

Front 272

What factors should be considered when selecting an intermediate frequency?
A. Cross-modulation distortion and interference.
B. Interference to other serves.
C. Image rejection and selectivity.
D. Noise figure and distortion.

Back 272

C. Image rejection and selectivity.

Front 273

What is the primary purpose of the first IF amplifier stage in a receiver?
A. Noise figure performance.
B. Tune out cross-modulation distortion.
C. Dynamic response.
D. Selectivity.

Back 273

D. Selectivity.

Front 274

What parameter must be selected when designing an audio filter using an op-amp?
A. Bandpass characteristics.
B. Desired current gain.
C. Temperature coefficient.
D. Output-offset overshoot.

Back 274

A. Bandpass characteristics.

Front 275

What are the distinguishing features of a Chebyshev filter?
A. It has a maximally flat response over its passband.
B. It only requires inductors.
C. It allows ripple in the passband.
D. A filter whose product of the series-and shunt-element impedances is a content for all frequencies.

Back 275

C. It allows ripple in the passband.

Front 276

When would it be more desirable to use an m-derived filter over a constant-k filter?
A. when the response must be maximally flat at one frequency.
B. When the number of components must be minimized.
C. When high power levels must be filtered.
D. When you need more attenuation at a certain frequency that is too close to the cut-off frequency for a constant-k filter.

Back 276

D. When you need more attenuation at a certain frequency that is too close to the cut-off frequency for a constant-k filter.

Front 277

A good crystal band-pass filter for a single-sideband phone would be?
A. 5 KHz.
B. 2.1 KHz.
C. 500 Hz.
D. 15 KHz.

Back 277

B. 2.1 KHz.

Front 278

Which statement is true regarding the filter output characteristics shown in Figure 3F16?
A. C is a low pass curve and B is a band pass curve.
B. B is a high pass curve and D is a low pass curve.
C. A is a high pass curve and B is a low pass curve.
D. A is a low pass curve and D is a band stop curve.

Back 278

D. A is a low pass curve and D is a band stop curve.

Front 279

What are the three general groupings of filters?
A. High-pass, low-pass and band-pass.
B. Inductive, capacitive and resistive.
C. Audio, radio and capacitive.
D. Hartley, Colpitts and pierce.

Back 279

A. High-pass, low-pass and band-pass.

Front 280

What is an m-derived filter?
A. A filter whose input impedance varies widely over the design bandwidth.
B. A filter whose product of the series- and shunt-element impedances is a constant for all frequencies.
C. A filter whose schematic shape is the letter "M".
D. A filter that uses a trap to attenuate undesired frequencies too near cutoff for a constant-k filter.

Back 280

D. A filter that uses a trap to attenuate undesired frequencies too near cutoff for a constant-k filter.

Front 281

What is an advantage of a constant-k filter?
A. It has high attenuation of signals at frequencies far removed from the pass band.
B. It can match impedances over a wide range of frequencies.
C. It uses elliptic functions.
D. The ratio of the cutoff frequency to the trap frequency can be varied.

Back 281

A. It has high attenuation of signals at frequencies far removed from the pass band.

Front 282

What are the distinguishing features of a Butterworth filter?
A. A filter whose product of the series- and shunt-element impedances is a constant for all frequencies.
B. It only requires capacitors.
C. It has a maximally flat response over its passband.
D. It requires only inductors.

Back 282

C. It has a maximally flat response over its passband.

Front 283

What is a product detector?
A. It provides local oscillations for input to the mixer.
B. It amplifies and narrows the band-pass frequencies.
C. It uses a mixing process with a locally generated carrier.
D. It is used to detect cross-modulation products.

Back 283

C. It uses a mixing process with a locally generated carrier.

Front 284

Which circuit is used to detect FM-phone signals?
A. Balanced modulator.
B. Frequency discriminator.
C. Product detector.
D. Phase splitter.

Back 284

B. Frequency discriminator.

Front 285

What is the process of detection o=in a radio diode detector circuit?
A. Breakdown of the Zener voltage.
B. Mixing with noise in the transition region of the diode.
C. Rectification and filtering of RF.
D. The change of reactance in the diode with respect to frequency.

Back 285

C. Rectification and filtering of RF.

Front 286

What is a frequency discriminator in a radio receiver?
A. A circuit for detecting FM signals.
B. A circuit for filtering two closely adjacent signals.
C. an automatic band switching circuit.
D. An FM generator.

Back 286

A. A circuit for detecting FM signals.

Front 287

In a CTCSS controlled FM receiver, the CTCSS tone is filtered out after the:
A. IF stage but before the mixer.
B. Mixer but before the IF.
C. IF but before the discriminator.
D. Discriminator but before the audio section.

Back 287

D. Discriminator but before the audio section.

Front 288

What is the definition of detection in a radio receiver?
A. The process of masking out the intelligence on a received carrier to make an S-meter operational.
B. The recovery of intelligence from the modulated RF signal.
C. The modulation of a carrier.
D. The mixing of noise with the received signal.

Back 288

B. The recovery of intelligence from the modulated RF signal.

Front 289

What is the digital signal processing term for noise subtraction circuitry?
A. Adaptive filtering and autocorrelation.
B. Noise blanking.
C. Noise limiting.
D. Auto squelch noise reduction.

Back 289

A. Adaptive filtering and autocorrelation.

Front 290

What is the purpose of de-emphasis in the receiver audio stage?
a. When coupled with the transmitter pre-emphasis, flat audio is achieved.
B. When coupled with the transmitter pre-emphasis, flat audio and noise reduction is received.
C. No purpose is achieved.
D. To conserve bandwidth by squelching no-audio periods in the transmission.

Back 290

B. When coupled with the transmitter pre-emphasis, flat audio and noise reduction is received.

Front 291

What makes a Digital Coded Squelch work?
A. Noise.
B. Tones.
C. Absence of noise.
D. Digital codes.

Back 291

D. Digital codes.

Front 292

What causes a squelch circuit to function?
A. Presence of noise.
B. Absence of noise.
C. Received tones.
D. Received digital codes.

Back 292

A. Presence of noise.

Front 293

What makes a CTCSS squelch work?
A. Noise.
B. Tones.
C. Absence of noise.
D. Digital codes.

Back 293

B. Tones.

Front 294

What radio circuit samples analog signals, records and processes them as numbers, then converts them back to analog signals?
A. The pre-emphasis audio stage.
B. The squelch gate circuit.
C. The digital signal processing circuit.
D. The voltage controlled oscillator circuit.

Back 294

C. The digital signal processing circuit.

Front 295

Where would you normally find a low-pass filter in a radio receiver?
A. In the AVC circuit.
B. In the Oscillator stage.
C. In the Power Supply.
D. A and C, but not B.

Back 295

D. A and C, but not B.

Front 296

How can ferrite beads be used to suppress ignition noise? Install them:
A. In the resistive high voltage cable every 2 years.
B. Between the starter solenoid and the starter motor.
C. Install them in the primary and secondary ignition leads.
D. In the antenna lead.

Back 296

C. Install them in the primary and secondary ignition leads.

Front 297

What is the term used to refer to the condition where the signals from a very strong station are superimposed on other signals being received?
A. Intermodulation distortion.
B. Cross-modulation interference.
C. Receiver quieting.
D. Capture effect.

Back 297

B. Cross-modulation interference.

Front 298

What is cross-modulation interference?
A. Interference between two transmitters of different modulation type.
B. Interference caused by audio rectification in the receiver preamp.
C. Modulation from an unwanted signal heard in addition to the desired signal.
D. Harmonic distortion of the transmitted signal.

Back 298

C. Modulation from an unwanted signal heard in addition to the desired signal.

Front 299

In Figure 3F15 at what point in the circuit (labeled 1 through 4) could a DC voltmeter be used to monitor signal strength?
A. 1
B. 2
C. 3
D. 4

Back 299

D. 4

Front 300

Pulse type interference to automobile radio receivers that appears related to the speed of the engine can often be reduced by:
A. Installing resistances in series with spark plug wires.
B. Using heavy conductors between the starting battery and the starting motor.
C. Connecting resistances in series with the battery.
D. Grounding the negative side of the battery

Back 300

A. Installing resistances in series with spark plug wires.

Front 301

What class of amplifier is distinguished by the presence of output throughout the entire signal cycle and the input never goes intot he cutoff region?
A. Class A.
B. Class B.
C. Class C.
D. Class D.

Back 301

A. Class A.

Front 302

What is the distinguishing feature of a Class A amplifier?
A. Output for less than 180 degrees of the signal cycle.
B. Output for the entire 360 degrees of the signal cycle.
C. Output for more than 180 degrees and less than 360 degrees of the signal cycle.
D. Output for exactly 180 degrees of the input signal cycle.

Back 302

B. Output for the entire 360 degrees of the signal cycle.

Front 303

Which class of amplifier has the highest linearity and least distortion?
A. Class A.
B. Class B.
C. Class C.
D. Class AB.

Back 303

A. Class A.

Front 304

Which class of amplifier provides the highest efficiency?
A. Class A.
B. Class B.
C. Class C.
D. Class AB.

Back 304

C. Class C.

Front 305

What class of amplifier is distinguished by the bias being set well beyond cutoff?
A. Class A.
B. Class C
C. Class B.
D. Class AB.

Back 305

B. Class C.

Front 306

Which class of amplifier has an operating angle of more than 180 degrees but less than 360 degrees when driven by a sine wave signal?
A. Class A.
B. Class B.
C. Class C.
D. Class AB.

Back 306

D. Class AB.

Front 307

The class B amplifier output is present for what portion of the input cycle?
A. 360 degrees.
B. Greater than 180 degrees and less than 360 degrees.
C. Less than 180 degrees.
D. 180 degrees.

Back 307

D. 180 degrees.

Front 308

What input-amplitude parameter is most valuable in evaluating the signal-handling capability of a Class A amplifier?
A. Average voltage.
B. RMS voltage.
C. Peak voltage.
D. Resting voltage.

Back 308

C. Peak voltage.

Front 309

The class C amplifier output is present for what portion of the input cycle?
A. Less than 180 degrees.
B. Exactly 180 degrees.
C. 360 degrees.
D. More than 180 but less than 360 degrees.

Back 309

A. Less than 180 degrees.

Front 310

What is the approximate DC input power to a Class AB RF power amplifier stage in an unmodulated carrier transmitter when the PEP output power is 500 watts?
A. 250 watts.
B. 600 watts.
C. 800 watts.
D. 1000 watts.

Back 310

D. 1000 watts.

Front 311

The class AB amplifier output is present for what portion of the input cycle?
A. Exactly 180 degrees.
B. 360 degrees
C. More than 180 but less than 360 degrees.
D. Less than 180 degrees.

Back 311

C. More than 180 but less than 360 degrees.

Front 312

What class of amplifier is characterized by conduction for 180 degrees of the input wave?
A. Class A.
B. Class B.
C. Class C.
D. Class D.

Back 312

B. Class B.

Front 313

What is the modulation index in an FM phone signal having a maximum frequency deviation of 3,000 Hz on either side of the carrier frequency when the modulating frequency is 1,000 Hz?
A. 0.3
B. 3,000
C. 3
D. 1,000

Back 313

C. 3

Front 314

What is the modulation index of a FM phone trnsmitter producing a maximum carrier deviation of 6 kHz when modulated with a 2 kHz modulating frequency?
A. 3
B. 6,000
C. 2,000
D. 1

Back 314

A. 3

Front 315

What is the total bandwidth of a FM phone trnasmission having a 5 kHz deviation and a 3 kHz modulating frequency?
A. 3 kHz.
B. 8 kHz.
C. 5 kHz.
D. 16 kHz.

Back 315

D. 16 kHz.

Front 316

How does the modulation index of a phase-modulated emission vary with RF carrier frequency?
A. It does not depend of the RF carrier frequency.
B. Modulation index increases as the RF carrier frequency increases.
C. It varies with the square root of the RF carrier frequency.
D. It decreases as the RF carrier frequency increases.

Back 316

A. It does not depend on the RF carrier frequency.

Front 317

How can a single-sideband phone signal be generated?
A. By driving a product detector with a DSB signal.
B. By using a reactance modulator followed by a mixer.
C. By using a loop modulator followed by a mixer.
D. By using a balanced modulator followed by a filter.

Back 317

D. By using a balanced modulator followed by a filter.

Front 318

What is a blanched modulator?
A. An FM modulator that produces a blanched deviation.
B. A modulator that produces a double sideband, suppressed carrier signal.
C. A modulator that produces a single sideband, suppressed carrier signal.
D. A modulator that produces a full carrier signal.

Back 318

B. A modulator that produces a double sideband, suppressed carrier signal.

Front 319

What is an L-network?
A. A low power Wi-Fi RF network connection.
B. A network consisting of an inductor and a capacitor.
C. A "lossy" network.
D. A network formed by joining two low pass filter.

Back 319

B. A network consisting of an inductor and a capacitor.

Front 320

What is a pi-network?
A. A network consisting of a capacitor, resistor and inductor.
B. The phase inversion stage.
C. An enhanced token ring network.
D. A network consisting of one inductor and two capacitors or two inductors and one capacitor.

Back 320

D. A networks consisting of one inductor and two capacitors or two inductors and one capacitor.

Front 321

What is the resonant frequency in an electrical circuit?
A. The frequency at which capacitive reactance equals inductive reactance.
B. The highest frequency that will pass current.
C. The lowest frequency that will pass current.
D. The frequency at which power factor is at a minimum.

Back 321

A. The frequency at which capacitive reactance equals inductive reactance.

Front 322

Which three network types are commonly used to match an amplifying device to a transmission line?
A. Pi-C network, pi network and T network.
B. T network, M network and Z network.
C. L network, pi network and pi-L network.
D. L network, pi network and C network.

Back 322

C. L network, pi network and pi-L network.

Front 323

What is a pi-L network?
A. A phase Inverter Load network.
B. A network consisting of two inductors and two capacitors.
C. A network with only three discrete parts.
D. A matching network in which all components are isolated from ground.

Back 323

B. A network consisting of two inductors and two capacitors.

Front 324

Which network provides the greatest harmonic suppression?
A. L network.
B. Pi network.
C. Pi-L network.
D. Inverse L network.

Back 324

C. Pi-L network.

Front 325

What will occur when a non-linear amplifier is used with a single-sideband phone transmitter?
A. Reduced amplifier efficiency.
B. Increased intelligibility.
C. Sideband inversion.
D. Distortion.

Back 325

D. Distortion.

Front 326

To produce a single-sideband suppressed carrier transmission it is necessary to ___ the carrier and to ___ the unwanted sideband.
A. Filter, filter.
B. Cancel, filter.
C. Filter, cancel.
D. Cancel, cancel.

Back 326

B. Cancel, filter.

Front 327

In a single-sideband phone signal, what determines the PEP-to-average power ratio?
A. The frequency of the modulating signal.
B. The degree of carrier suppression.
C. The speech characteristics.
D. The amplifier power.

Back 327

C. The speech characteristics.

Front 328

What is the approximate ratio of peak envelope power to average power during normal voice modulation peak in a single-sideband phone signal?
A. 2.5 to 1.
B. 1 to 1.
C. 25 to 1.
D. 100 to 1.

Back 328

A. 2.5 to 1.

Front 329

What is the output peak envelope power from a transmitter as measured on an oscilloscope showing 200 volts peak-to-peak across a 50-ohm load resistor?
A. 1,000 watts.
B. 100 watts.
C. 200 watts.
D. 400 watts.

Back 329

B. 100 watts.

Front 330

What would be the voltage across a 50-ohm dummy load dissipating 1,200 watts?
A. 245 volts.
B. 692 volts.
C. 346 volts.
D. 173 volts.

Back 330

A. 245 volts.

Front 331

How can intermodulation interference between two transmitter in close proximity often be reduced or eliminated?
A. By using a Class C final amplifier with high driving power.
B. By installing a terminated circulator or ferrite isolator in the feed line to the transmitter and duplexer.
C. By installing a band-pass filter in the antenna feed line.
D. By installing a low-pass filter in the antenna feed line.

Back 331

B. By installing a terminated circulator or ferrite isolator in the feed line to the transmitter and duplexer.

Front 332

How can parasitic oscillations be eliminated in a power amplifier?
A. By tuning for maximum SWR.
B. By tuning for maximum power output.
C. By neutralization.
D. By tuning the output.

Back 332

C. By neutralization.

Front 333

What is the name of the condition that occurs when the signals of two transmitters in close proximity mix together in one or both of their final amplifiers, and unwanted signals at the sum and difference frequencies of the original transmissions are generated?
A. Amplifier desensitization.
B. Neutralization.
C. Adjacent channel interference.
D. Intermodulation interference.

Back 333

D. Intermodulation interference.

Front 334

What term describes a wide-bandwidth communications system in which the RF carrier varies according to some pre-determined sequence?
A. Spread-spectrum communication.
B. AMTOR.
C. SITOR.
D. Time-domain frequency modulation.

Back 334

A. Spread-spectrum communication.

Front 335

how can even-order harmonics be reduced or prevented in transmitter amplifier design?
A. By using a push-push amplifier.
B. By operating class C.
C. By using a push-pull amplifier.
D. By operating class AB.

Back 335

C. By using a push-pull amplifier.

Front 336

What is the modulation type that can be a frequency hopping of one carrier or multiple simultaneous carriers?
A. SSB.
B. FM.
C. OFSK.
D. Spread spectrum.

Back 336

D. Spread spectrum.

Front 337

The deviation ratio is the :
A. Audio modulating frequency to the center carrier frequency.
B. Maximum carrier frequency deviation tot he highest audio modulation frequency.
C. Carrier center frequency to the audio modulating frequency.
D. Highest audio modulating frequency frequency to the average audio modulating frequency.

Back 337

B. Maximum carrier frequency deviation to the highest audio modulating frequency.

Front 338

What is the deviation ratio for an FM phone signal having a maximum frequency deviation of plus or minus 5 kHz and accepting a maximum modulation rate of 3 kHz?
A. 60
B. 0.16
C. 0.6
D. 1.66

Back 338

D. 1.66

Front 339

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz and accepting a maximum modulation rate of 3.5 kHz?
A. 2.14
B. 0.214
C. 0.47
D. 47

Back 339

A. 2.14

Front 340

How can an FM-phone signal be produced in a transmitter?
A. By modulating the supply voltage to a class-B amplifier.
B. By modulating the supply voltage to a class-C amplifier.
C. By using a balanced modulator.
D. By feeding the audio directly to the oscillator.

Back 340

D. By feeding the audio directly to the oscillator.

Front 341

What is meant by the term odulation index?
A. The ratio between the deviation of a frequency modulated signal and the modulating frequency.
B. The processor index.
C. The FM signal-to-noise ratio.
D. The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency.

Back 341

A. The ratio between the deviation of a frequency modulated signal and the modulating frequency.

Front 342

In a FM-phone signal, what is the term for the maximum deviation from the carrier frequency divided by the maximum audio modulating frequency?
A. Deviation index.
B. Modulation index.
C. Deviation ratio.
D. Modulation ratio.

Back 342

C. Deviation ratio.

Front 343

In Figure 3H17, the block labeled 4 would indicate that this schematic is most likely a/an:
A. Audio amplifier.
B. Shipboard RADAR.
C. SSB radio transmitter.
D. Wireless LAN (local area network) computer.

Back 343

C. SSB radio transmitter.

Front 344

In Figure 3H17, which block diagram symbol (labeled 1 through 4) represents where audio intelligence is inserted?
A. 1
B. 2
C. 3
D. 4

Back 344

B. 2

Front 345

What kind of input signal could be used to test the amplitude linearity of a single-sideband phone transmitter while viewing the output on an oscilloscope?
A. Whistling in the microphone.
B. An audio frequency sine wave.
C. A two-tone audio-frequency sine wave.
D. An audio frequency square wave.

Back 345

C. A two-tone audio-frequency sine wave.

Front 346

What does a two-tone test illustrate on an oscilloscope?
A. Linearity of a SSB transmitter.
B. Frequency of the carrier phase shift.
C. Percentage of frequency modulation.
D. sideband suppression.

Back 346

A. Linearity of a SSB transmitter.

Front 347

How can a double-sideband phone signal be produced?
A. By using a reactance modulator.
B. By varying the voltage to the varactor in an oscillator circuit.
C. By using a phase detector, oscillator, and filter in a feedback loop.
D. By modulating the supply voltage to a class C amplifier.

Back 347

D. By modulating the supply voltage to a class C amplifier.

Front 348

What type of signals are used to conduct an SSB two-tone test?
A. Two audio signals of the same frequency, but shifted 90 degrees in phase.
B. Two non-harmonically related audio signals that are within the modulation band pass of the transmitter.
C. Two different audio frequency square wave signals of equal amplitude.
D. Any two audio frequencies as long as they are harmonically related.

Back 348

B. Two non-harmonically related audio signals that are within the modulation band pass of the transmitter.

Front 349

What is an important factor in pulse-colde modulation using time-division multiplex?
A. Synchronization of transmit and receive clock pulse rates.
B. Frequency separation.
C. Overmodulation and undermodulation.
D. Slight variations in power supply voltage.

Back 349

A. Synchronization of transmit and receive clock pulse rates.

Front 350

In a pulse-width modulation system, what parameter does the modulating signal vary?
A. Pulse frequency.
B. Pulse duration.
C. Pulse amplitude.
D. Pulse intensity.

Back 350

B. Pulse duration.

Front 351

What is the name of the type of modulation in which the modulating signal varies the duration of the transmitted pulse?
A. Amplitude modulation.
B. Frequency modulation.
C. Pulse-height modulation.
D. Pulse-width modulation.

Back 351

D. Pulse-width modulation.

Front 352

Which of the following best describes a pulse modulation system?
A. The peak transmitter power is normally much greater than the average power.
B. Pulse modulation is sometimes used in SSB voice transmitters.
C. The average power is normally only slightly below the peak power.
D. The peak power is normally twice as high as the average power.

Back 352

A. The peak transmitter power is normally much greater than the average power.

Front 353

In a pulse-position modulation system, what parameter does the modulating signal vary?
A. The number of pulses per second.
B. The time at which each pulse occurs.
C. Both the frequency and amplitude of the pulses.
D. The duration of the pulses.

Back 353

B. The time at which each pulses occurs.

Front 354

What is one way that voice is transmitted in a pulse-width modulation system?
A. A standard pulse is varied in amplitude by an amount depending on the voice waveform at that instant.
B. The position of a standard pulse is varied by an amount depending on the voice waveform at that instant.
C. A standard pulse is varied in duration by an amount depending on the voice waveform at that instant.
D. The number of standard pulses per second varies depending on the voice waveform at that instant.

Back 354

C. A standard pulse is varied in duration by an amount depending on the voice waveform at that instant.

Front 355

When a lead-acid storage battery is being charged, a harmful effect to humans is:
A. Internal plate sulfation may occur under constant charging.
B. Emission of oxygen.
C. Emission of chlorine gas.
D. Emission of hydrogen gas.

Back 355

D. Emission of hydrogen gas.

Front 356

A battery with a terminal voltage of 12.5 volts is to be trickle-charged at a 0.5 A rate. What resistance should be connected in series with the battery to charge it from a 110-V DC line?
A. 95 ohms.
B. 300 ohms.
C. 195 ohms.
D. None of these

Back 356

C. 195 ohms.

Front 357

What capacity in amperes does a storage battery need to be in order to operate a 50 watt transmitter for 6 hours? Assume a continuous trnasmitter load of 70% of the key-locked demand of 40 A, and an emergency light load of 1.5 A.
A. 100 ampere-hours.
B. 177 ampere-hours.
C. 249 ampere-hours.
D. None of these

Back 357

B. 177 ampere-hours.

Front 358

What is the total voltage when 12 Nickel-Cadmium batteries are connected in series?
A. 12 volts.
B. 12.6 volts.
C. 15 volts.
D. 72 volts.

Back 358

C. 15 volts.

Front 359

The average fully-charged voltage of a lead-acid storage cell is:
A. 1 volt.
B. 1.2 volts.
C. 1.56 volts.
D. 2.06 volts.

Back 359

D. 2.06 volts.

Front 360

A nickel-cadmium cell has an operating voltage of about:
A. 1.25 volts.
B. 1.4 volts.
C. 1.5 volts.
D. 2.1 volts.

Back 360

A. 1.25 volts.

Front 361

When an emergency transmitter uses 325 watts and a receiver uses 50 watts, how many hours can a 12.6 volts, 55 ampere-hour battery supply full power to both units?
A. 1.8 hours.
B. 6 hours.
C. 3 hours.
D. 1.2 hours.

Back 361

A. 1.8 hours.

Front 362

What current will flow in a 6 volt storage battery with an internal resistance of 0.01 ohms, when a 3-watt, 6-volt lamp is connected?
A. 0.4885 amps.
B. 0.4995 amps.
C. 0.5566 amps.
D. 0.5795 amps.

Back 362

B. 0.4995 amps.

Front 363

A ship RADAR unit uses 315 watts and a radio uses 50 watts. If the equipment is connected to a 50 ampere-hour battery rated at 12.6 volts, how long will the battery last?
A. 1 hour 43 minutes.
B. 28.97 hours.
C. 29 minutes.
D. 10 hours, 50 minutes.

Back 363

A. 1 hour 43 minutes.

Front 364

If a marine radiotelephone receiver uses 75 watts of power and a transmitter uses 325 watts, how long can they both operate before discharging a 50 ampere-hour 12 volt battery?
A. 40 minutes.
B. 1 hour.
C. 1 1/2 hours.
D. 6 hours.

Back 364

C. 1 1/2 hours.

Front 365

A 6 volt battery with 1.2 ohms internal resistance is connected across two light bulbs in parallel whose resistance is 12 ohms each. What is the current flow?
A. 0.57 amps.
B. 0.83 amps.
C. 1.0 amps.
D. 6.0 amps.

Back 365

B. 0.83 amps.

Front 366

A 12.6 volt, 8 ampere-hour battery is supplying power to a receiver that uses 50 watts and a RADAR system that uses 300 watts. How long will the battery last?
A. 100.8 hours.
B. 27.7 hours.
C. 1 hour
D. 17 minutes or 0.3 hours.

Back 366

D. 17 minutes or 0.3 hours.

Front 367

What occurs if the load is removed from an operating series DC motor?
A. It will stop running.
B. Speed will increase slightly.
C. No change occurs.
D. It will accelerate until it falls apart.

Back 367

D. It will accelerate until it falls apart.

Front 368

If a shunt motor running with a load has its shunt field opened, how would this affect the speed of the motor?
A. It will slow down.
B. It will stop suddenly.
C. It will speed up.
D. It will be unaffected.

Back 368

C. It will speed up.

Front 369

The expression "voltage regulation" as it applies to a shunt-wound DC generator operating at a constant frequency refers to:
A. Voltage fluctuations from load to no-load.
B. Voltage output efficiency.
C. Voltage in the secondary compared to the primary.
D. Rotor winding voltage ratio.

Back 369

A. Voltage fluctuations from load to no-load.

Front 370

What is the line current of a 7 horsepower motor operating on 120 volts at full load, a power factor or 0.8, and 95 efficient?
A. 4.72 amps.
B. 13.03 amps.
C. 56 amps.
D. 57.2 amps.

Back 370

D. 57.2 amps.

Front 371

A 3 horsepower, 100 V DC motor is 85% efficient when developing its rated output. What is the current?
A. 8.545 amps.
B. 20. 345 amps.
C. 26.300 amps.
D. 25.000 amps.

Back 371

C. 26. 300 amps.

Front 372

The output of a separately-excited AC generator running at a constant speed can be controlled by:
A. The armature.
B. The amount of field current.
C. The brushes.
D. The exciter.

Back 372

B. The amount of field current.

Front 373

Which of the following could cause a high standing wave ratio on a transmission line?
A. Excessive modulation.
B. An increase in output power.
C. A detuned antenna coupler.
D. Low power from the transmitter.

Back 373

C. A detuned antenna coupler.

Front 374

Why is the value of the radiation resistance of an antenna important?
A. Knowing the radiation resistance makes it possible to match impedances for maximum power transfer.
B. Knowing the radiation resistance makes it possible to measure the near-field radiation density from transmitting antenna.
C. The value of the radiation resistance represents the front-to-side ratio fo the antenna.
D. The value of the radiation resistance represents the front-to-back ratio of the antenna.

Back 374

A. Knowing the radiation resistance makes it possible to match impedances for maximum power transfer.

Front 375

A radio frequency device that allows RF energy to pass through in one direction with very little loss but absorbs RF power in the opposite direction is a:
A. Circulator.
B. Wave trap.
C. Multiplexer.
D. Isolator.

Back 375

D. Isolator.

Front 376

What is an advantage of using a trap antenna?
A. It may be used for multiband operation.
B. It has high directivity in the high-frequency bands.
C. it has high gain.
D. It minimizes harmonic radiation.

Back 376

A. It may be used for multiband operation.

Front 377

What is meant by the term radiation resistance of an antenna?
A. Losses in the antenna elements and feed line.
B. The specific impedance of the antenna.
C. The resistance in the trap coils to received signals.
D. An equivalent resistance that would dissipate the same amount of power as that radiated from an antenna.

Back 377

D. An equivalent resistance that would dissipate the same amount of power as that radiated from an antenna.

Front 378

What is meant by the term antenna bandwidth?
A. Antenna length divided by the number of elements.
B. The frequency range over which an antenna can be expected to perform well.
C. The angle between the half-power radiation points.
D. The angle formed between two imaginary lines drawn through the ends of the elements.

Back 378

B. The frequency range over which an antenna can be expected to perform well.

Front 379

What is the current flowing through a 52 ohm line with an input of 1,872 watts?
A. 0.06 amps.
B. 6 amps.
C. 28.7 amps.
D. 144 amps.

Back 379

B. 6 amps.

Front 380

The voltage produced in a receiving antenna is:
A. Out of phase with the current if connected properly.
B. Out of phase with the current if cut to 1/3 wavelength.
C. Variabel depending on the station's SWR.
D. Always proportional to the received field strength.

Back 380

D. Always proportional to the received field strength.

Front 381

Which of the following represents the best standing wave ratio (SWR)?
A. 1:1.
B. 1:1.5.
C. 1:3
D. 1:4.

Back 381

A. 1:1.

Front 382

AT THE ENDS OF A HALF-WAVE ANTENNA, WHAT VALUES OF CURRENT AND VOLTAGE EXIST COMPARED TO THE REMAINDER OF THE ANTENNA?
A. Equal voltage and current.
B. Minimum voltage and maximum current.
C. Maximum voltage and minimum current.
D. Minimum voltage and minimum current.

Back 382

C. Maximum voltage and minimum current.

Front 383

An antenna radiates a primary signal of 500 watts output. If there is a 2nd harmonic output of 0.5 watt, what attenuation of the 2nd harmonic has occurred?
A. 10dB.
B. 30 dB.
C. 40 dB.
D. 50 dB.

Back 383

B. 30dB.

Front 384

There is an improper impedance match between a 30 watt transmitter and the antenna, with 5 watts reflected. How much power is actually radiated?
A. 35 watts.
B. 30 watts.
C. 25 watts.
D. 20 watts.

Back 384

C. 25 watts.

Front 385

A vertical 1/4 wave antenna receives signals:
A. In the microwave band.
B. In one vertical direction.
C. In one horizontal direction.
D. Equally from all horizontal directions.

Back 385

D. Equally from all horizontal directions.

Front 386

The resonant frequency of a Hertz antenna can be lowered by:
A. Lowering the frequency of the transmitter.
B. Placing an inductance in series with the antenna.
C. Placing a condenser in series with the antenna
D. Placing a resistor in series with the antenna.

Back 386

B. Placing an inductance in series with the antenna.

Front 387

An excited 1/2 wavelength antenna produces:
A. Residual fields.
B. An electro-magnetic field only.
C. Both electro-magnetic and electro-static fields.
D. An electro-flux field sometimes.

Back 387

C. Both electro-magnetic and electro-static fields.

Front 388

To increase the resonant frequency of a 1/4 wavelength antenna:
A. Add a capacitor in series.
B. Lower capacitor value.
C. Cut antenna.
D. Add an inductor.

Back 388

A. Add a capacitor in series.

Front 389

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?
A. It is increased.
B. It is decreased.
C. No change occurs.
D. It becomes flat.

Back 389

B. It is decreased.

Front 390

To lengthen an antenna electrically, add a:
A. Coil.
B. Resistor.
C. Battery.
D. Conduit.

Back 390

A. Coil

Front 391

What is the meaning of the term velocity factor of a transmission line?
A. The ratio of the characteristic impedance of the line to the terminating impedance.
B. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum.
C. The velocity of the wave on the transmission line multiplied by the velocity of light in a vacuum.
D. The index of shielding for coaxial cable.

Back 391

B. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum.

Front 392

What determines the velocity factor in a transmission line?
A. The termination impedance.
B. The line length.
C. Dielectrics in the line.
D. The center conductor resistivity.

Back 392

C. Dielectrics in the line.

Front 393

Nitrogen is placed in transmission lines to:
A. Improve the "skin-effect" of microwaves.
B. Reduce arcing in the line.
C. Reduce the standing wave ratio of the line.
D. Prevent moisture from entering the line.

Back 393

D. Prevent moisture from entering the line.

Front 394

A perfect (no loss) coaxial cable has 7 dB of reflected power when the input is 5 watts. What is the output of the transmission line?
A. 1 watt.
B. 1.25 watts.
C. 2.5 watts.
D. 5 watts.

Back 394

A. 1 watt.

Front 395

Referred to the fundamental frequency, a shorted stub line attached to the transmission line to absorb even harmonics could have a wavelength of:
A. 1.41 wavelength.
B. 1/2 wavelength.
C. 1/4 wavelength.
D. 1/6 wavelength.

Back 395

C. 1/4 wavelength.

Front 396

If a transmission line has a power loss of 6 dB per 100 feet, what is the power at the feed point to the antenna at the end of a 200 foot transmission line fed by a 100 watt transmitter?
A. 70 watts.
B. 50 watts.
C. 25 watts.
D. 6 watts.

Back 396

D. 6 watts.

Front 397

What is the effective radiated power of a repeater with 50 watts transmitter power output, 4 dB feed line loss, 3 dB duplexer and circulator loss, and 6 dB antenna gain?
A. 158 watts.
B. 39.7 watts.
C. 251 watts.
D. 69.9 watts.

Back 397

B. 39.7 watts.

Front 398

What is the effective radiated power of a repeater with 75 watts transmitter power output, 4 dB feedline loss, 3 dB duplexer and circulator loss, and 10 dB antenna gain?
A. 600 watts.
B. 75 watts.
C. 18.75 watts.
D. 150 watts.

Back 398

D. 150 watts.

Front 399

What is the effective radiated power of a repeater with 75 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 6 dB antenna gain?
A. 37.6 watts.
B. 237 watts.
C. 150 watts.
D. 23.7 watts.

Back 399

A. 37.6 watts.

Front 400

What is the effective radiated power of a repeater with 100 watts transmitter power output , 4 dB feline loss, 3 dB duplexer and circulator loss, and 7 dB antenna gain?
A. 631 watts.
B. 400 watts.
C. 25 watts.
D. 100 watts.

Back 400

D. 100 watts.

Front 401

Wha tis the effective radiated power of a repeater with 100 watts transmitter power output, 5 dB feed line loss, 4 dB duplexer and circulator loss, and 10 dB antenna gain?
A. 126 watts.
B. 800 watts.
C. 12.5 watts.
D. 1260 watts.

Back 401

A. 126 watts.

Front 402

What is the effective radiated power of a repeater with 50 watts transmitter power output, 5 dB feed line loss, 4 dB duplexer and circulator loss, and 7 dB antenna gain?
A. 300 watts.
B. 315 watts.
C. 31.5 watts.
D. 69.9 watts.

Back 402

C. 31.5 watts.

Front 403

What is the frequency range of the Distance Measuring Equipment (DME) used to indicate an aircraft's slant range distance to a selected ground-based navigation station?
A. 108.00 MHz to 117.95 MHz.
B. 108.10 MHz to 111.95 MHz.
C. 962 MHz to 1213 MHz.
D. 329.15 MHz to 335.00 MHz.

Back 403

C. 962 MHz to 1213 MHz.

Front 404

the Distance Measuring Equipment (DME) measures the distance from the aircraft to the DME ground station. This is referred to as:
A. DME bearing.
B. The slant range.
C. Glide Slope angle of approach.
D. Localizer course width.

Back 404

B. The slant range.

Front 405

The Distance Meausring Equipment (DME) ground station has a built-in delay between reception of an interrogation and transmission of the reply to allow:
A. Someone to answer the call.
B. The VOR to make a mechanical hook-up.
C. Operation at close range.
D. Clear other traffic for a reply.

Back 405

C. Operation at close range.

Front 406

What is the main underlying operating principle of an aircraft's Distance Measuring Equipment (DME)?
A. A measurable amount of time is required to send and receive a radio signal through the Earth's atmosphere.
B. The difference between the peak values of two DC voltages may be used to determine an aircraft's distance to another aircraft.
C. A measurable frequency compression of an AC signal may be used to determine an aircraft's distance to the exit ramp of an airports runway.
D. A phase inversion between two AC voltages may be used to determine an aircrafts distance to the exit ramp of an airports runway.

Back 406

A. A measurable amount of time is required to send and receive a radio signal through the Earth's atmosphere.

Front 407

What radio mavigation aid determines the distance from an aircraft to a selected VORTAC station by measuring the length of time the radio signal takes to travel to and from the station?
A. RADAR.
B. Loran C.
C. Distance Marking (DM).
D. Distance Measuring Equipment (DME).

Back 407

D. Distance Measuring Equipment (DME).

Front 408

the majority of airborne Distance Measuring Equipment systems automatically tune their transmitter and receiver frequencies to the paired ____/____ channel.
A. VOR/marker beacon.
B. VOR/LOC.
C. Marker beacon/glideslope.
D. LOC/glideslope.

Back 408

B. BOR/LOC.

Front 409

All directions associated with a VOR station are related to:
A. Magnetic north.
B. North pole.
C. North star.
D. None of these.

Back 409

A. Magnetic north.

Front 410

The rate that the transmitted VOR variable signal rotates is equivalent to how many revolutions per second?
A. 60.
B. 30.
C. 2400.
D. 1800.

Back 410

B. 30.

Front 411

What is the frequency range of the ground-based Very-high-frequency Omnidirectional Range (VOR) stations used for aircraft navigation?
A. 108.00 kHz to 117.95 kHz.
B. 329.15 MHz to 335.00 MHz.
C. 329.15 kHz to 335.00 kHz.
D. 108.00 MHz to 117.95 MHz.

Back 411

D. 108.00 MHz to 117.95 MHz.

Front 412

Lines drawn from the VOR station in a particular magnetic direction are:
A. Radials.
B. Quadrants.
C. Bearings.
D. Headings.

Back 412

A. Radials.

Front 413

The amplitude modulated variable phase signal and the frequency modulated reference phase signal of a Very-high-frequency Omnidirectional Range (VOR) station used for aircraft navigation are synchronized so that both signals are in phase with each other at ________ of the VOR station.
A. 180 degrees South, true bearing position.
B. 360 degrees North, magnetic baring position.
C. 180 degrees South, magnetic bearing position.
D. 0 degrees North, true bearing position.

Back 413

B. 360 degrees North, magnetic bearing position.

Front 414

What is the main underlying operating principle of the Very-high-frequency Omnidirectional Range (VOR) aircraft navigational system?
A. A definite amount of time is requried to send and receive a radio signal.
B. The difference between the peak values of two DC voltages may be used to determine an aircraft's altitude above a selected VOR station.
C. A phase difference between two AC voltages may be used to determine an aircraft's azimuth position in relation to a selected VOR station.
D. A phase difference between two AC voltages may be used to determine an aircraft's distance from a selected VOR station.

Back 414

C. A phase difference between two AC voltages may be used to determine an aircraft's azimuth position in relation to a selected VOR station.

Front 415

What is the frequency range of the localizer beam system used by aircraft to find the centerline of a runway during an Instrument Landing System (ILS) approach to an airport?
A. 108.10 kHz to 111.95 kHz.
B. 329.15 MHz to 335.00 MHz.
C. 329.15 kHz to 335.00 kHz.
D. 108.10 MHz to 111.95 MHz.

Back 415

D. 108.10 MHz to 111.95 MHz.

Front 416

What is the frequency range of the marker beacon system used to indicate an aircraft's position during an Instrument Landing System (ILS) approach to an airport's' runway?
A. The outer, middle, and inner marker beacons' UHF frequencies are unique for each ILS equipped airport to provide unambiguous frequency-protected reception areas in the 329.15 to 335.00 MHz range.
B. The outer marker beacon's carrier frequency is 400 MHz, the middle marker beacon's carrier frequency is 1300 MHz, and the inner marker beacon's carrier frequency is 3000 MHz.
C. The outer, the middle, and the inner marker beacon's carrier frequencies are all 75 MHz but the marker beacons are 95% tone-modulated at 400 Hz (outer), 1300 Hz (middle), and 3000 Hz (inner).
D. The outer, marker beacon's carrier frequency is 3000 kHz, the middle marker beacon's carrier frequency is 1300 kHz, and the inner marker beacon's carrier frequency is 400 kHz.

Back 416

C. The outer, the middle, and the inner marker beacon's carrier frequencies are all 75 MHz but the marker beacons are 95% tone-modulated at 400 Hz (outer), 1300 Hz (middle), and 3000 Hz (inner).

Front 417

Which of the following is a requried compoent of an Instrument Landing System (ILS)?
A. Altimeter: shows aircraft height above sea-level.
B. Localizer: shows aircraft deviation horizontally from center of runway.
C. VHF Communications: provide communications to aircraft.
D. Distance Measuring Equipment: shows aircraft distance to VORTAC station.

Back 417

B. Localizer: shows aircraft deviation horizontally from center of runway.

Front 418

What type of antenna is used is an aircraft's Instrument Landing System (ILS) glideslope installation?
A. A vertically polarized antenna that radiates an omnidirectional antenna pattern.
B. A balanced loop reception antenna.
C. A folded dipole reception antenna.
D. An electronically steerable phased-array antenna that radiates a directional antenna pattern.

Back 418

C. A folded dipole reception antenna.

Front 419

Choose the only correct statement about the localizer beam system used by aircraft to find the centerline of a runway during an Instrument Landing System(ILS) approach to an airport. The localizer beam system:
A. Operates within the assigned frequency range of 108.10 to 111.95 GHz.
B. Produces two amplitude modulated antenna patterns; one pattern above and one pattern below the normal 2.5 degree approach glide path of the aircraft.
C. Frequencies are automatically tuned-in when the proper glide slope frequency is selected on the aircraft's Navigation and Communication (NAV/COMM) transceiver.
D. Produces two amplitude modulated antenna patterns; one pattern with an audio frequency of 90 Hz and one pattern with an audio frequency of 150 Hz, one left of the runway centerline and one right of the runway centerline.

Back 419

D. Produces two amplitude modulated antenna patterns; one pattern with an audio frequency of 90 Hz and one pattern with an audio frequency of 150 Hz, one left of the runway centerline and one right of the runway centerline.

Front 420

On runway approach, an ILS Localizer shows:
A. Deviation left or right of runway center line.
B. Deviation up and down from ground speed.
C. Deviation percentage from authorized ground speed.
D. Wind speed along runway.

Back 420

A. Deviation left or right of runway center line.

Front 421

What is the frequency range of an aircraft's Automatic Direction Finding (ADF) equipment?
A. 190 kHz to 1750 kHz
B. 190 MHz to 1750 MHz
C. 108.10 MHz to 111.95 MHz
D. 108.00 MHz to 117.95 MHz

Back 421

A. 190 kHz to 1750 kHz

Front 422

What is meant by the term "night effect" when using an aircraft's Automatic Direction Finding(ADF) equipment? Night effect refers to the fact that:
A. All Non Directional Beacon (NDB) transmitters are turned-off at dusk and turned-on at dawn.
B. Non Directional Beacon (NDB) transmissions can bounce-off the Earth's ionosphere at night and be received at almost any direction.
C. An aircraft's ADF transmission will be slowed at night due to the increased density of the Earth's atmosphere after sunset.
D. An aircraft's ADF antennas usually collect dew moisture after sunset which decreases their effective reception distance from an NDB transmitter.

Back 422

B. Non Directional Beacon (NDB) transmissions can bounce-off the Earth's ionosphere at night and be received at almost any direction.

Front 423

What are the transmit and receive frequencies of an aircraft's mode C transponder operating in the Air Traffic Control RADAR Beacon System (ATCRBS)?
A. Transmit at 1090 MHz, and receive at 1030 MHz
B. Transmit at 1030 kHz, and receive at 1090 kHz
C. Transmit at 1090 kHz, and receive at 1030 kHz
D. Transmit at 1030 MHz, and receive at 1090 MHz

Back 423

A. Transmit at 1090 MHz, and receive at 1030 MHz

Front 424

In addition to duplicating the functions of a mode C transponder, an aircraft's mode S transponder can also provide:
A. Primary RADAR surveillance capabilities.
B. Long range lightning detection.
C. Mid-air collision avoidance capabilities.
D. Backup VHF voice communications abilities.

Back 424

C. Mid-air collision avoidance capabilities.

Front 425

What type of encoding is used in an aircraft's mode C transponder transmission to a ground station of the Air Traffic Control RADAR Beacon System (ATCRBS)?
A. Differential phase shift keying
B. Pulse position modulation
C. Doppler effect compressional encryption
D. Amplitude modulation at 95%

Back 425

B. Pulse position modulation

Front 426

Choose the only correct statement about an aircraft's Automatic Direction Finding (ADF) equipment.
A. An aircraft's ADF transmission exhibits primarily a line-of-sight range to the ground-based target station and will not follow the curvature of the Earth.
B. Only a single omnidirectional sense antenna is required to receive and NDB transmission and process the signal to calculate the aircraft's bearing to the selected ground station.
C. All frequencies in the ADF's operating range except the commercial standard broadcast stations (550 to 1660 kHz) can be utilized as a navigational Non Directional Beacon (NDB) signal.
D. All aircraft's ADF antennas can receive transmissions that are over the Earth's horizon (sometimes several hundred miles away) since these signals will follow the curvature of the Earth.

Back 426

D. All aircraft's ADF antennas can receive transmissions that are over the Earth's horizon (sometimes several hundred miles away) since these signals will follow the curvature of the Earth.

Front 427

What type of antenna pattern is radiated from a ground station phased-array directional antenna when transmitting the PPM pulses in a Mode S interrogation signal of an aircraft's Traffic alert and Collision Avoidance System (TCAS) installation?
A. 1090 MHz directional pattern
B. 1030 MHz omnidirectional pattern
C. 1090 MHz omnidirectional pattern
D. 1030 MHz directional pattern

Back 427

D. 1030 MHz directional pattern

Front 428

What type of antenna is used in an aircraft's Instrument Landing System (ILS) marker beacon installation?
A. An electronically steerable phased-array antenna that radiates a directional antenna pattern.
B. A folded dipole reception antenna
C. A balanced loop reception antenna
D. A horizontally polarized antenna that radiates and omnidirectional antenna pattern.

Back 428

C. A balanced loop reception antenna

Front 429

What is the frequency range of an aircraft's Very High Frequency (VHF) communications?
A. 118.000 MHz to 136.975 MHz (worldwide up to 151.975 MHz)
B. 108.00 MHz to 117.95 MHz
C. 329.15 MHz to 335.00 MHz
D. 2.000 MHz to 29.999 MHZ

Back 429

A. 118.000 MHz to 136.975 MHz (worldwide up to 151.975 MHz)

Front 430

Aircraft Emergency Locator Transmitters (ELT) operate on what frequencies?
A. 121.5 MHz
B. 243 MHz
C. 121.5 and 243 MHz
D. 121.5, 243, and 406 MHz

Back 430

D. 121.5, 243, and 406 MHz

Front 431

What is the frequency range of an aircraft's radio altimeter?
A. 962 MHz to 1213 MHz
B. 329.15 MHz to 335.00 MHz
C. 4250 MHz to 4350 MHz
D. 108.00 MHz to 117.95 MHz

Back 431

C. 4250 MHz to 4350 MHz

Front 432

What type of antenna is attached to an aircraft's Mode C transponder installation adn used to receive 1030 MHz interrogation signals from the Air Traffic Control RADAR Beacon System (ATCRBS)?
A. An electronically steerable phased-array directional antenna
B. An L-band monopole blade-type omnidirectional antenna
C. A folded dipole reception antenna
D. An internally mounted, mechanically rotatable loop antenna

Back 432

B. An L-band monopole blade-type omnidirectional antenna

Front 433

Some aircraft and avionics equipment operates with a prime power line frequency of 400 Hz. What is the principle advantage of a higher line frequency?
A. 400 Hz power supplies draw less current than 60 Hz supplies allowing more current available for other systems on the aircraft.
B. A 400 Hz power supply generates less heat and operates much more efficiently than a 60 Hz power supply.
C. The magnetic devices in a 400 Hz power supply such as transformers, chokes and filters are smaller and lighter than those used in 60Hz power supplies.
D. 400 Hz power supplies are much less expensive to produce than power supplies with lower line frequencies.

Back 433

C. The magnetic devices in a 400 Hz power supply such as transformers, chokes and filters are smaller and lighter than those used in 60Hz power supplies.

Front 434

Aviation services use predominantly (blank) microphones.
A. Dynamic
B. Carbon
C. Condenser
D. Piezoelectric crystal

Back 434

A. Dynamic

Front 435

Typical airborne HF transmitters usually provide a nominal RF power output to the antenna of (blank) watts, compared with (blank) watts RF output from a typical VHF transmitter.
A. 10, 50
B. 50, 10
C. 20, 100
D. 100, 20

Back 435

D. 100, 20

Front 436

Before ground testing an aircraft RADAR, the operator should:
A. Ensure that the area in front of the antenna is clear of other maintenance personnel to avoid radiation hazards.
B. Be sure the receiver has been properly shielded and grounded.
C. First test the transmitter to a matched load.
D. Measure the power supply voltages to prevent circuit damage.

Back 436

A. Ensure that the area in front of the antenna is clear of other maintenance personnel to avoid radiation hazards.

Front 437

What type of antenna is used in an aircraft's Very High Frequency Omnidirectional Range (VOR) and Localizer (LOC) installations?
A. Vertically polarized antenna that radiates an omnidirectional antenna pattern.
B. Horizontally polarized omnidirection reception antenna.
C. Balanced loop transmission antenna.
D. Folded dipole reception antenna.

Back 437

B. Horizontally polarized omnidirection reception antenna.

Front 438

What is the function of a commercial aircraft's SELCAL installation? SELCAL is a type of aircraft communications ___________?
A. Device that allows an aircraft's receiver to be continuously calibrated for signal selectivity.
B. System where a ground-based transmitter can call a selected aircraft or group of aircraft without the flight crew monitoring the ground-station frequency.
C. Transmission that uses sequential logic algorithm encryption to prevent public "eavesdropping' of crucial aircraft flight data.
D. System where an airborne transmitter can selectively calculate the line-of-sight distance to several ground-station receivers.

Back 438

B. System where a ground-based transmitter can call a selected aircraft or group of aircraft without the flight crew monitoring the ground-station frequency.

Front 439

What is a 1/2 digit on a DMM?
A. Smaller physical readout on the left side of the display.
B. Partial extended accuracy on lower part of the range.
C. Smaller physical readout on the right side.
D. Does not apply to DMMs.

Back 439

B. Partial extended accuracy on lower part of the range.

Front 440

A 50 microampere meter movement has an internal resistance of 2,000 ohms. What applied voltage is required to indicate half-scale defection?
A. 0.01 volts
B. 0.10 volts
C. 0.005 volts
D. 0.05 volts

Back 440

D. 0.05 volts

Front 441

What is the purpose of a series multiplier resistor used with a voltmeter?
A. It is used to increase the voltage-indicating range of the voltmeter.
B. A multiplier resistor is not used with a voltmeter.
C. It is used to decrease the voltage-indicating range of the voltmeter.
D. It is used to increase the current-indicating range of an ammeter, not a voltmeter.

Back 441

A. It is used to increase the voltage-indicating range of the voltmeter.

Front 442

What is the purpose of a shunt resistor used with an ammeter?
A. A shunt resistor is not used with an ammeter.
B. It is used to decrease the ampere indicating range of the ammeter.
C. It is used to increase the ampere indicating range of the ammeter.
D. It is used to increase the voltage indicating range of the voltmeter, not the ammeter.

Back 442

C. It is used to increase the ampere indicating range of the ammeter.

Front 443

What instrument is used to indicate high and low digital voltage states?
A. Ohmmeter.
B. Logic probe.
C. Megger.
D. Signal strength meter.

Back 443

B. Logic probe.

Front 444

What instrument may be used to verify proper radio antenna functioning?
A. Digital ohm meter
B. Hewlett-Packard frequency meter.
C. An SWR meter.
D. Different radio.

Back 444

C. An SWR meter.

Front 445

How is a frequency counter used?
A. To provide reference points on an analog receiver dial thereby aiding in the alignment of the receiver.
B. To heterodyne the frquency being measured with a known variable frequency oscillator until zero beat is achieved, thereby indicating the unknown frequency.
C. To measure the deviation in an FM transmitter in order to determine the percentage of modulation.
D. To measure the time between event, or the frequency, which is the reciprocal of the time.

Back 445

D. To measure the time between events, or the frequency, which is the reciprocal of the time.

Front 446

What is a frequency standard?
A. A well-known (standard) frequency used for transmitting certain messages.
B. A device used to produce a highly accurate reference frequency.
C. A device for accurately measuring frequency to within 1 Hz.
D. A device used to generate wide-band random frequencies.

Back 446

B. A device used to produce a highly ac curate reference frequency.

Front 447

What equipment may be useful to track down EMI aboard a ship or aircraft?
A. Fluke multimeter.
B. An oscilloscope.
C. Portable AM receiver.
D. A logic probe.

Back 447

C. Portable AM receiver.

Front 448

On an analog wattmeter, what part of the scale is most accurate and how much does that accuracy extend to the rest of the reading scale?
A. The accuracy is only at full scale, and that absolute number reading is carried through to the rest of the range. The upper 1/3 of the meter is the only truly calibrated part.
B. The accuracy is constant throughout the entire range of the meter.
C. The accuracy is only there at the upper 5% of the meter, and is not carried through at any other reading.
D. The accuracy cannot be determined at any reading.

Back 448

A. The accuracy is only at full scale, and that absolute number reading is carried through to the rest of the range. The upper 1/3 of the meter is the only truly calibrated part.

Front 449

Which of the following frequency standards is used as a time base standard by field technicians?
A. Quartz Crystal.
B. Rubidium Standard.
C. Cesium Beam Standard.
D. LC Tank Oscillator.

Back 449

B. Rubidium Standard.

Front 450

Which of the following contains a multirange AF voltmeter calibrated in dB and a sharp, internal 1000 Hz bandstop filter, both used in conjunction with each other to perform quieting tests?
A. SINAD meter.
B. Reflectometer.
C. Dip meter.
D. Vector-impedance meter.

Back 450

A. SINAD meter.

Front 451

What is used to decrease circuit loading when using an oscilloscope?
A. Dual input amplifiers.
B. 10:1 divider probe.
C. Inductive probe.
D. Resistive probe.

Back 451

B. 10:1 divider probe.

Front 452

How does a spectrum analyzer differ from a conventional oscilloscope?
A. The oscilloscope is used to display electrical signals while the spectrum analyzer is used to measure ionospheric refection.
B. The oscilloscope is used to display electrical signals in the frequency domain while spectrum analyzer is used to display electrical signals in the time domain.
C. The oscilloscope is used to display electrical signals in the time domain while the spectrum analyzer is used to display electrical signals in the frequency domain.
D. The oscilloscope is used for displaying audio frequencies and the spectrum analyzer is used for displaying radio frequencies.

Back 452

C. The oscilloscope is used to display electrical signals in the time domain while the spectrum analyzer is used to display electrical signals in the frequency domain.

Front 453

What stage determines the maximum frequency response of an oscilloscope?
A. Time base.
B. Horizontal sweep.
C. Power supply.
D. Vertical amplifier.

Back 453

D. Vertical amplifier.

Front 454

What factors limit the accuracy, frequency response, and stability of an oscilloscope?
A. Sweep oscillator quality and defection amplifier bandwidth.
B. Tube face voltage increments and deflection amplifier voltage.
C. Sweep oscillator quality and tube face voltage increments.
D. Deflection amplifier output impedance and tube face frequency increments.

Back 454

A. Sweep oscillator quality and deflection amplifier bandwidth.

Front 455

An oscilloscope can be used to accomplish all of the following except:
A. Measure electron flow with the aid of a resistor.
B. Measure phase difference between two signals.
C. Measure velocity of light with the aid of a light emitting diode.
D. Measure electrical voltage.

Back 455

C. Measure velocity of light with the aid of a light emitting diode.

Front 456

What instrument is used to check the signal quality of a single-sideband radio transmission?
A. Field strength meter.
B. Signal level meter.
C. Sidetone monitor.
D. Oscilloscope.

Back 456

D. Oscilloscope.

Front 457

A(n)_____and_______can be combined to measure the characteristics of transmission lines. Such an arrangement is known as a time-domain reflectometer (TDR).
A. Frequency spectrum analyzer, RF generator.
B. Oscilloscope, pulse generator.
C. AC millivolt meter, AF generator.
D. Frequency counter, linear detector.

Back 457

B. Oscilloscope, pulse generator.

Front 458

What does the horizontal axis of a spectrum analyzer display?
A. Amplitude.
B. Voltage.
C. Resonance.
D. Frequency.

Back 458

D. Frequency.

Front 459

What does the vertical axis of a spectrum analyzer display?
A. Amplitude.
B. Duration.
C. Frequency.
D. Time.

Back 459

A. Amplitude.

Front 460

What instrument is most accurate when checking antennas and transmission lines at the operating frequency of the antenna?
A. Time domain reflectometer.
B. Wattmeter.
C. DMM
D. Frequency domain reflectometer.

Back 460

D. Frequency domain reflectometer.

Front 461

What test instrument can be used to display spurious signals in the output of a radio transmitter?
A. A spectrum analyzer.
B. A wattmeter.
C. A logic analyzer.
D. A time domain reflectometer.

Back 461

A. A spectrum analyzer.

Front 462

What instrument is commonly used by radio service technicians to monitor frequency, modulation, check receiver sensitivity, distortion, and to generate audio tones?
A. Oscilloscope.
B. Spectrum analyzer.
C. Service monitor.
D. DMM.

Back 462

C. Service monitor.

Front 463

Can a P25 radio system be monitored with a scanner?
A. Yes , regardless if it has P25 decoding or not.
B. No.
C. Yes, if the scanner P25 decoding.
D. Yes, but it must also have P26 decoding.

Back 463

C. Yes, if the scanner P25 decoding.

Front 464

Which of the following answers is true?
A. The RF Power reading on a CDMA (code division multiple access) radio will be very accurate on an analog power meter.
B. The RF Power reading on a CDMA radio is not accurate on an analog power meter.
C. Power cannot be measured using CDMA modulation.
D. None of the above.

Back 464

B. The RF Power reading on a CDMA radio is not accurate on an analog power meter.

Front 465

What is a common method used to program radios without using a "weird" connection?
A. Banding.
B. using the ultraviolet from a programmed radio to repeat the programming in another.
C. Infra-red communication.
D. Having the radio maker send down a programming signal via satellite.

Back 465

C. Infra-red communications.

Front 466

What is the common method for determining the exact sensitivity specification of a receiver?
A. Measure the recovered audio for 12 dB of SINAD.
B. Measure the recovered audio for 10 dB of quieting.
C. Measure the recovered audio for 10 dB of SINAD.
D. Measure the recovered audio for 25 dB of quieting.

Back 466

A. Measure the recovered audio for 12 dB of SINAD.

Front 467

A communications technician would perform a modulation-acceptance bandwidth test in order to :
A. Ascertain the audio frequency response of the receiver.
B. Determine whether the CTCSS in the receiver is operating correctly.
C. Verify the results from a 12 dB SINAD test.
D. Determine the effective bandwidth of a communications receiver.

Back 467

D. Determine the effective bandwidth of a communications receiver.

Front 468

What is the maximum FM deviation for voice operation of a normal wideband channel on VHF and UHF?
A. 2.5 kHz
B. 5.0 kHz.
C. 7.5 kHz
D. 10 kHz

Back 468

B. 5.0 kHz

Front 469

When soldering or working with CMOS electronics products or equipment, a wrist strap:
A. Must have less than 100.000 ohms of resistance to prevent static electricity.
B. Cannot be used when repairing TTL devices.
C. Must be grounded to a water pipe.
D. Does not work well in conjunction with anti-static floor mats.

Back 469

A. Must have less than 100,000 ohms of resistance to prevent static electricity.

Front 470

Which of the following is the preferred method of cleaning solder from plated-through circuit-board holes?
A. Use a dental pick.
B. Use a vacuum device.
C. Use a soldering iron tip that has a temperature above 900 degrees F.

Back 470

B. Use a vacuum device.

Front 471

What is the proper way to cut plastic wire ties?
A. With scissors.
B. With a knife.
C. With semi-flush diagonal pliers.
D. With flush-cut diagonal pliers and cut flush.

Back 471

D. With flush-cut diagonal pliers and cut flush.

Front 472

The ideal method of removing insulation from wire is:
A. The thermal stripper.
B. The pocket knife.
C. A mechanical wire stripper.
D. The scissor action stripping tool.

Back 472

A. The thermal stripper.

Front 473

A "hot gas bonder" is used:
A. To apply solder to the iron tip while it is heating the component.
B. For non-contact melting of solder.
C. To allow soldering both sides of the PC board simultaneously.
D. To cure lCA adhesives.

Back 473

B. FOR NON-CONTACT MELTING OF SOLDER.

Front 474

When repairing circuit board assemblies it is most important to:
A. Use a dental pick to clear plated-though holes.
B. Bridge broken copper traces with solder.
C. Wear safety glasses.
D. Use a holding fixture.

Back 474

C. Wear safety glasses.

Front 475

What color is the binder for pairs 51-75 in a 100-pair cable?
A. Red
B. Blue
C. Black
D. Green

Back 475

D. Green

Front 476

What is most important when routing cables in a mobile unit?
A. That cables be cut to the exact length.
B. Assuring accessibility of the radio for servicing from outside the vehicle.
C. Assuring radio or electronics cables do not interfere with the normal operation of the vehicle.
D. Assuring cables are concealed under floor mats or carpeting.

Back 476

C. Assuring radio or electronics cables do not interfere with the normal operation of the vehicle.

Front 477

Why should you not use white or translucent plastic tie wraps on a radio tower?
A. White tie wraps are not AA approved.
B. UV radiation from the sun deteriorates the plastic very quickly.
C. The white color attracts wasps
D. The black tie wraps may cause electrolysis.

Back 477

B. UV radiation from the sun deteriorates the plastic very quickly.

Front 478

What is the 6th pair color code in a 25 pair switchboard cable as is found in building telecommunications interconnection?
A. Blue/Green, Green/Blue.
B. Red/Blue, White/Violet.
C. Red/Blue, Blue/Red.
D. White/Slate, Slate/White.

Back 478

C. Red/Blue, Blue/Red.

Front 479

What tolerance off of plumb should a single base station radio rack be installed?
A. No tolerance allowed.
B. Just outside the bubble on a level.
C. All the way to one end.
D. Just inside the bubble on a level.

Back 479

D. Just inside the bubble on a level.

Front 480

What type of wire would connect an SSB automatic tuner to an insulated backstay?
A. A. GTO-15 high-voltage cable.
B. RG8U
C. RG213.
D. 16-gauge two-conductor.

Back 480

A. GTO-15 high-voltage cable.

Front 481

On a 150 watt marine SSB HF transceiver, what would be indicated by a steady output of 75 watts when keying the transmitter on?
A. There is probably a defect in the system causing the carrier to be transmitted.
B. One of the sidebands is missing.
C. Both sidebands are being transmitting.
D. The operation is normal.

Back 481

A. There is probably a defect in the system causing the carrier to be transmitted.

Front 482

The tachometer of a building's elevator circuit experiences interference caused by the radio system nearby. What is a common potential "fix" for the problem?
A. Replace the tachometer of the elevator.
B. Add a .01 µF capacitor across the motor/tachometer leads.
C. Add a 200 µF capacity across the motor/tachometer leads.
D. Add an isolating resistor in series with the motor leads.

Back 482

B. Add a .01 µF capacitor across the motor/tachometer leads.

Front 483

A common method of programming portable or mobile radios is to use a:
A. A laptop computer
B. Dummy load.
C. A wattmeter.
D. a signal generator.

Back 483

A. A laptop computer.

Front 484

In a software-defined transceiver, what would be the best way for a technician to make a quick overall evaluation of the radio's operational condition?
A. Set up a spectrum analyzer and service monitor and manually verify the manufacturer's specifications.
B. Use another radio on the same frequency to check the transmitter.
C. Use the built-in self-test feature.
D. Using on-board self-test routines are strictly prohibited by the FCC in commercial transmitters. Amateur Radio is the only service currently authorized to use them.

Back 484

C. Use the built-in self-test feature.

Front 485

How might an installer verify correct GPS sentence to marine DSC VHF radio?
A. Press and hold the red distress button.
B. Look for latitude and longitude on the display.
C. Look for GPS confirmation readout.
D. Ask for VHF radio check position report.

Back 485

B. Look for latitude and longitude on the display.

Front 486

What steps must be taken to activate the DSC emergency signaling function on a marine VHF?
A. Separate 12 volts to the switch.
B. Secondary DSC transmit antenna.
C. GPS position input.
D. input of registered 9-digit MMSI.

Back 486

D. Input of registered 9-digit MMSI.

Front 487

What term describes a wide-bandwith communications system in which the RF carrier frequency varies according to some predetermined sequence?
A. Amplitude commandeered single sideband.
B. SITOR.
C. Time-domain frequency modulation.
D. Spread spectrum communication.

Back 487

D. Spread spectrum communication.

Front 488

Name two types of spread spectrum systems used in most RF communications applications?
A. AM and FM.
B. QPSK or QAM.
C. Direct Sequence and Frequency Hopping.
D. Frequency Hopping and APSK.

Back 488

C. Direct Sequence and Frequency Hopping.

Front 489

What is the term used to describe a spread spectrum communications system where the center frequency of a conventional carrier is altered many times per sec on in accordance with a pseudo-random list of channels?
A. Frequency hopping.
B. Direct sequence.
C. Time-domain frequency modulation.
D. Frequency compandored spread spectrum.

Back 489

A. Frequency hopping.

Front 490

A TDMA radio uses what to carry the multiple conversations sequentially?
A. Separate frequencies
B. Separate pilot tones
C. Separate power levels
D. Separate time slots

Back 490

D. Separate time slots

Front 491

Which of the following statements about SSB voice transmissions is correct?
A. The use A3E emission which are produced by modulating the final amplifier.
B. They use F3E emission which is produced by phase shifting the carrier.
C. They normally use J3E emissions, which consist of one sideband and a suppressed carrier.
D. They may use A1A emission to suppress the carrier.

Back 491

C. They normally use J3E emissions, which consist of one sideband and a suppressed carrier.

Front 492

What are the two most-used PCS (Personal Communications Systems) coding techniques used to separate different calls?
A. QPSK and QAM
B. CDMA and GSM
C. ABCD and SYZ
D. AM and Frequency Hopping

Back 492

B. CDMA and GSM

Front 493

What is a CODEC?
A. A device to read Morse code.
B. A computer operated digital encoding compandor.
C. A coder/decoder IC or circuitry that converts a voice signal into a predetermined digital format for encrypted transmission.
D. A voice amplitude compression chip.

Back 493

C. A coder/decoder IC or circuitry that converts a voice signal into a predetermined digital format for encrypted transmission.

Front 494

The GSM (Global System for Mobile Communications) uses what type of CODEC for digital mobile radio system communications?
A. Regular-Pulse Excited (RPE)
B. Code-Excited Linear Predictive (CLEP)
C. Multi-Pulse Excited (MPE)
D. Linear Excited Code (LEC)

Back 494

A. Regular-Pulse Excited (RPE)

Front 495

Which of the following codes has gained the widest acceptance for exchange of data from one computer to another?
A. Gray
B. Baudot
C. Morse
D. ASCII

Back 495

D. ASCII

Front 496

The International Organization for Standardization has developed a seven-level reference mode for a packet-radio communications structure. What level is responsible for the actual transmission of data and handshaking signals.
A. The physical layer
B. The transport layer
C. The communications layer
D. The synchronization layer

Back 496

A. The physical layer

Front 497

What CODEC is used in Phase 2 P25 radios?
A. IWCE
B. IMBC
C. IMMM
D. AMBE

Back 497

D. AMBE

Front 498

The International Organization for Standardization has developed a seven-layer reference model for packets-radio communications structure. The (blank) level arranges the bits into frames and controls data flow.
A. Transport layer
B. Link layer
C. Synchronization layer
D. Communications layer

Back 498

B. Link layer

Front 499

What is a SDR?
A. Software Deviation Radio
B. Software Defined Radio
C. SWR Meter
D. Static Dynamic Ram

Back 499

B. Software Defined Radio

Front 500

What does the DSP not do in a modern DSP radio?
A. Control frequency
B. Control modulation
C. Control detection
D. Control SWR

Back 500

D. Control SWR

Front 501

Which statement best describes the code used for GDMSS-DSC transmissions?
A. A 10 bit error code starting with bits of data followed by a 3 bit error correcting code.
B. A 10 bit error correcting code starting with a 3 bit error correcting code followed by 7 bits of data.
C. An 8 bit code with 7 bits of data followed by a single parity bit.
D. A 7 bit code that is transmitted twice for error correction.

Back 501

A. A 10 bit error code starting with bits of data followed by a 3 bit error correcting code.

Front 502

Which is the code used for SITOR-A and -B transmissions?
A. The 5 bit baudot telex code.
B. Each character consists of 7 bits with 3 "zeros" and 4 "ones".
C. Each character consists of 7 bits with 4 "zeros" and 3 "ones".
D. Each character has 7 bits of data and 3 bits for error correction.

Back 502

C. Each character consists of 7 bits with 4 "zeros" and 3 "ones".

Front 503

Which of the following statements is true?
A. The Signal Repetition character (1001100) is used as a control signal in SITOR-ARQ.
B. The Idle Signal (a) (0000111) is used for FEC Phasing Signal 1.
C. The Idle Signal (b) (0011001) is used for FEC Phasing Signal 2.
D. The Control Signal 1 (0101100) is used to determine the time displacement in SITOR-B.

Back 503

B. The Idle Signal (a) (0000111) is used for FEC Phasing Signal 1.

Front 504

What principle allows multiple conversations to be able to share one radio channel on a GSM channel.
A. Frequency Division Multiplex
B. Double sideband
C. Time Division Multiplex
D. None of the above

Back 504

C. Time Division Multiplex

Front 505

What is the cannel spacing used for VHF marine radio?
A. 10 kHz.
B. 12.5 kHz.
C. 20 kHz.
D. 25 kHz.

Back 505

D. 25 kHz.

Front 506

What VHF channel is assigned for distress and calling?
A. 70
B. 16
C. 21A
D. 68

Back 506

B. 16

Front 507

What VHF Channel is used for Digital Selective Calling and acknowledgement?
A. 16
B. 21A
C. 70
D. 68

Back 507

C. 70

Front 508

Maximum allowable frequency deviation for VHF marine radios is:
A. +/- 5 kHz.
B. +/- 15 kHz.
C. +/- 2.5 kHz.
D. +/- 25 kHz.

Back 508

A. +/- 5 kHz.

Front 509

What is the reason for the USA-INT control or function?
A. It changes channels that are normally simplex channels into duplex channels.
B. It changes some channels that are normally duplex channels into simples channels.
C. When the control is set to "INT" the range is increased.
D. None of these.

Back 509

B. It changes some channels that are normally duplex channels into simplex channels.

Front 510

How might an installer verify correct GPS sentence to marine DSC VHF radio?
A. Look for latitude and longitude, plus speed, on VHF display.
B. press and hold the red distress button.
C. Look for gaps CONFIRMATION READOUT.
D. ASK FOR vhf RADIO CHECK POSTION REPORT.

Back 510

A. Look for latitude and longitude, plus speed, on VHF display.

Front 511

What is a common occurrence when voice-testing an SSB aboard a boat?
A. Ammeter fluctuates down with each spoken word.
B. Voltage panel indicator lamps may glow with each syllable.
C. Automatic tuner cycles on each syllable.
D. Minimal voltage drop seen at power source.

Back 511

B. Voltage panel indicator lamps may glow with each syllable.

Front 512

What might contribute to apparent low voltage on marine SSB transmitting?
A. Blown red fuse.
B. Too much grounding.
C. Blown black negative fuse.
D. Antenna mismatch.

Back 512

C. Blown black negative fuse.

Front 513

What type of wire connects an SSB automatic tuner to an insulated backstay?
A. RG8U
B. RG213.
C. 16-gauge two-conductor.
D. GTO-15 high-voltage cable.

Back 513

D. GTO-15 high-voltage cable.

Front 514

Which of the following statements concerning SITOR communications is true?
A. ARQ message transmissions are made in data groups consisting of three-character blocks.
B. ARQ transmissions are acknowledged by the Information Receiving Station only at the end of the message.
C. ARQ communications rely upon error correction by time diversity transmission and reception.
D. Forward error correction is an interactive mode.

Back 514

A. ARQ message transmission are made in data groups consisting of three-character blocks.

Front 515

The sequence ARQ, FEC, SFEC best corresponds to which of the following sequences?
A. One-way communications to a single station, one-way communications to all stations, two-way communications.
B. One-way communications to all stations, two-way communications, one-way communications to a single station.
C. Two way communications, one-way communications to all stations, one-way communications to a single stations.
D. Two way communications, one-way communications to a single station, one-way communications to all stations.

Back 515

C. Two way communications, one-way communications to all stations, one-way communications to a single stations.

Front 516

Which of the following statements concerning SITOR communications is true?
A. Communication is established on the working channel and answer backs are exchanged before FEC broadcasts can be received.
B. In the ARQ mode each character is transmitted twice.
C. Weather broadcasts cannot be made in FEC because sending each character twice would cause the broadcast to be prohibitively long.
D. Two-way communication with the coast radio station using FEC is not necessary to be able to receive the broadcasts.

Back 516

D. Two-way communication with the coast radio station using FEC is not necessary to be able to receive the broadcasts.

Front 517

What causes the SART to begin a transmission?
A. When activated manually, it begins radiating immediately.
B. After being activated the SART responds to RADAR interrogation.
C. It is either manually or water activated before radiating.
D. It begins radiating only wen keyed by the operator.

Back 517

B. After being activated the SART responds to RADAR interrogation.

Front 518

How should the signal from a Search And Rescue Radar Transponder appear on a RADAR display?
A. A series of dashes.
B. A series of spirals all originating from the range and bearing of the SART.
C. A series of twenty dashes.
D. A series of 12 equally spaced dots.

Back 518

D. A series of 12 equally spaced dots.

Front 519

In which frequency band does a search and rescue transponder operate?
A. 9 GHz
B. 3 GHz
C. S-band
D. 406 MHz

Back 519

A. 9 GHz

Front 520

Which piece of required GMDSS equipment is the primary source of transmitting locating signals?
A. Radio Direction Finder (RDF).
B. A SART transmitting on 406 MHz.
C. Survival Craft Transceiver.
D. An EPIRB transmitting on 406 MHz.

Back 520

D. An EPIRB transmitting on 406 MHz.

Front 521

Which of the following statements concerning satellite EPIRBs is true?
A. Once activated, these EPIRBs transmit a signal for use in identifying the vessel and for determining the position of the beacon.
B. The coded signal identifies the nature of the distress situation.
C. The coded signal only identifies the vessel's name and port of registry.
D. If the GMDSS Radio Operator does not program the EPIRB, it will transmit default information such as the follow-on communications frequency and mode.

Back 521

A. Once activated, these EPIRBs transmit a signal for use in identifying the vessel and for determining the posit of the beacon.

Front 522

What statement is true regarding 406 MHz EPIRB transmissions?
A. Allows immediate voice communications with the RCC.
B. Coding permits the SAR authorities to know if manually or automatically activated.
C. Transmits a unique hexadecimal identification number.
D. Radio Operator programs an I.D into the SART immediately prior to activation.

Back 522

C. Transmits a unique hexadecimal identification number.

Front 523

What is facsimile?
A. The transmission of printed pictures by slow-scan television.
B. The transmission of characters by radio teletype that form a picture when printed.
C. The transmission of printed pictures for permanent display on paper.
D. The transmission of video by television.

Back 523

C. The transmission of printed pictures for permanent display on paper.

Front 524

What is the standard scan rate for high frequency 3 MHz - 23 MHz weather facsimile reception from shore stations.
A. 240 lines per minute
B. 120 lines per minute
C. 150 lines per second
D. 60 lines per second

Back 524

B. 120 lines per minute

Front 525

What would be the bandwidth of a good crystal lattice band-pass filter for weather facsimile HF (high frequency) reception?
A. 500 Hz at -6 dB
B. 6 kHz at - 6 dB
C. 1 kHz at -6 dB
D. 15 kHz at - 6 dB

Back 525

C. 1 kHz at -6 dB

Front 526

Which of the following statements about NAVTEX is true?
A. Receives MSI broadcasts using SITOR-B or FEC mode.
B. The ship station transmits on 518 kHz.
C. The ship receives MSI broadcasts using SITOR-A or ARQ mode.
D. NAVTEX is received on 2182 kHz using SSB.

Back 526

A. Receives MSI broadcasts using SITOR-B or FEC mode.

Front 527

Which of the following is the primary frequency that is used exclusively for NAVTEX broadcasts internationally?
A. 2187.5 kHz
B. 4209.5 kHz
C. VHF channel 16
D. 518 kHz

Back 527

D. 518 kHz

Front 528

What determines whether a NAVTEX receiver does not print a particular type of message context?
A. The message does not concern your vessel.
B. The subject indicator matches that programmed for rejection by the operator.
C. The transmitting station ID covering your area has not been programmed for rejection by the operator.
D. All messages sent during each broadcast are printed.

Back 528

B. The subject indicator matches that programmed for rejection by the operator.

Front 529

What data language is bi-directional, multi-transmitter, multi-receiver network?
A. NMEA 2000
B. NMEA 0181
C. NMEA 0182
D. NMEA 0183

Back 529

A. NMEA 2000

Front 530

How should shielding be grounded on an NMEA 0183 data line?
A. Unterminated at both ends.
B. Terminated to ground at the talker and unterminated at the listener.
C. Unterminated at the talker and terminated at the listener.
D. Terminated at both talker and listener.

Back 530

B. Terminated to ground at the talker and unterminated at the listener.

Front 531

What might occur in NMEA 2000 network topology if one device in line should fail?
A. The system shuts down until the device is removed.
B. Other electronics after the failed device will be inoperable.
C. The main fuse on the backbone may open.
D. There will be no interruption to all other devices.

Back 531

D. There will be no interruption to all other devices.

Front 532

In an NMEA 2000 device, a load equivalence number (LEN) of 1 is equivalent to how much current consumption?
A. 50 mA
B. 10 mA
C. 25 mA
D. 5 mA

Back 532

A. 50 mA

Front 533

An NMEA 2000 system with devices in single location may be powered using this method:
A. Dual mid-powered network
B. End powered network
C. Individual devices individually powered
D. No 12 volts needed for NMEA 2000 devices

Back 533

B. End powered network

Front 534

What voltage drop at the end of the last segment will satisfy NMEA 2000 network cabling plans?
A. 0.5 volts
B. 2.0 volts
C. 1.5 volts
D. 3.0 volts

Back 534

C. 1.5 volts

Front 535

What is the normal range of pulse repetition rates?
A. 2,000 to 4,000 pps
B. 1,000 to 3,000 pps
C. 500 to 1,000 pps
D. 500 to 2,000 pps

Back 535

D. 500 to 2,000 pps

Front 536

The RADAR range in nautical miles to an object can be found by measuring the elapsed time during a RADAR pulse and dividing this quantity by:
A. 0.87 seconds
B. 1.15 µs
C. 12.346 µs
D. 1.073 µs

Back 536

C. 12.346 µs

Front 537

What is the normal range of pulse widths?
A. .05 µs to 0.1 µs
B. .05 µs to 1.0 µs
C. 1.0 µs to 3.5 µs
D. 2.5 µs to 5.0 µs

Back 537

B. .05 µs to 1.0 µs

Front 538

Shipboard RADAR is most commonly operated in what band?
A. VHF
B. UHF
C. SHF
D. EHF

Back 538

C. SHF

Front 539

The pulse repetition rate (prr) of a RADAR refers to the :
A. Reciprocal of the duty cycle
B. Pulse rate of the local oscillator
C. Pulse rate of the klystron
D. Pulse rate of the magnetron

Back 539

D. Pulse rate of the magnetron

Front 540

If the elapsed time for a RADAR echo is 62 µs, what is the distance in nautical miles to the object?
A. 5 nm
B. 87 nm
C. 37 nm
D. 11.5 nm

Back 540

A. 5 nm

Front 541

The ATR box:
A. Prevents the received signal from entering the transmitter.
B. Protects the receiver from strong RADAR signals.
C. Turns off the receiver when the transmitter is on.
D. All of the above.

Back 541

A. Prevents the received signal from entering the transmitter.

Front 542

What is the purpose or function of the RADAR duplexer/circulator? It is a/an:
A. Coupling device that is used in the transition from a rectangular waveguide to a circular waveguide.
B. Electronic switch that allows the use of one antenna for both transmission and reception.
C. Modified length of waveguide that is used to sample a portion of the transmitted energy for testing purposes.
D. Dual section coupling device that allows the use of a magnetron as a transmitter.

Back 542

B. Electronic switch that allows the use of one antenna for both transmission and reception.

Front 543

What device can be used to determine the performance of a RADAR system at sea?
A. Echo box
B. Klystron
C. Circulator
D. Digital signal processor

Back 543

A. Echo box

Front 544

What is the purpose of a synchro transmitter and receiver?
A. Synchronizes the transmitted and received pulse trains.
B. Prevents the receiver from operating during the period of the transmitted pulse.
C. Transmits the angular position of the antenna to the indicator unit.
D. Keeps the speed of the motor generator constant.

Back 544

C. Transmits the angular position of the antenna to the indicator unit.

Front 545

Digital Signal Processing (DSP) of RADAR signals (compared with analog) causes:
A. Improved display graphics
B. Improved weak signal or target enhancement
C. Less interference with SONAR systems
D. Less interference with other radio communications equipment

Back 545

B. Improved weak signal or target enhancement

Front 546

The component or circuit providing the transmitter output power for a RADAR system is the:
A. Thyratron
B. SCR
C. Klystron
D. Magnetron

Back 546

D. Magnetron

Front 547

When a RADAR is being operated on the 48 mile range setting, what is the most appropriate pulse width (PW) and pulse repetition rate (pps)?
A. 1.0 µs PW and 2,000 pps
B. 0.05 µs PW and 2,000 pps
C. 2.5 µs PW and 2,500 pps
D. 1.0 µs PW and 500 pps

Back 547

D. 1.0 µs PW and 500 pps

Front 548

When a RADAR is being operated on the 6 mile range setting what is the most appropriate pulse width and pulse repetition rate?
A. 1.0 µs PW and 500 pps
B. 2.0 µs PW and 3,000 pps
C. 0.25 µs PW and 1,000 pps
D. 0.01 µs PW and 500 pps

Back 548

C. 0.25 µs PW and 1,000 pps

Front 549

We are looking at a target 25 miles away. When a RADAR is being operated on the 25 mile range setting what is the most appropriate pulse width and pulse repetition rate?
A. 1.0 µs PW and 500 pps
B. 0.25 µs PW and 1,000 pps
C. 0.01 µs PW and 500 pps
D. 0.05 µs PW and 2,000 pps

Back 549

A. 1.0 µs PW and 500 pps

Front 550

What pulse width and repetition rate should you use at long ranges?
A. Narrow pulse width and slow repetition rate
B. Narrow pulse width and fast repetition rate
C. Wide pulse width and fast repetition rate
D. Wide pulse width and slow repetition rate

Back 550

D. Wide pulse width and slow repetition rate

Front 551

What pulse width and repetition rate should you use at short ranges?
A. Wide pulse width and fast repetition rate
B. Narrow pulse width and slow repetition rate
C. Narrow pulse width and fast repetition rate
D. Wide pulse width and slow repetition rate

Back 551

C. Narrow pulse width and fast repetition rate

Front 552

When a RADAR is being operated on the 1.5 mile range setting, what is the most appropriate pulse width and pulse repetition rate?
A. 0.25 µs PW and 1,000 pps
B. 0.05 µs PW and 2,000 pps
C. 1.0 µs PW and 500 pps
D. 2.5 µs PW and 2,500 pps

Back 552

B. 0.05 µs PW and 2,000 pps

Front 553

How does the gain of a parabolic dish antenna change when the operating frequency is doubled?
A. Gain does not change
B. Gain is multiplied by 0.707
C. Gain increases 6 dB
D. Gain increases 3 dB

Back 553

C. Gain increases 6 dB

Front 554

What type of antenna or pickup device is used to extract the RADAR signal from the wave guide?
A. J-hook
B. K-hook
C. Folded dipole
D. Circulator

Back 554

A. J-hook

Front 555

What happens to the beamwidth of an antenna as the gain is increased? The beamwidth:
A. Increases geometrically as the gain is increased
B. Increases arithmetically as the gain is increased
C. Is essentially unaffected by the gain of the antenna
D. Decreases as the gain is increased.

Back 555

D. Decreases as the gain is increased.

Front 556

A common shipboard RADAR antenna is the:
A. Slotted array
B. Dipole
C. Stacked Yagi
D. Vertical Marconi

Back 556

A. Slotted array

Front 557

Conductance takes place in a waveguide:
A. By interelectron delay
B. Through electrostatic field reluctance
C. In the same manner as a transmission line
D. Through electromagnetic and electrostatic fields in the walls of the waveguide.

Back 557

D. Through electromagnetic and electrostatic fields in the walls of the waveguide.

Front 558

To couple energy into and out of a waveguide use:
A. Wide copper sheeting
B. A thin piece of wire as an antenna
C. An LC circuit
D. Capacitive coupling

Back 558

B. A thin piece of wire as an antenna

Front 559

The permanent magnetic field that surrounds a traveling-wave tube (TWT) is intended to:
A. Provide a means of coupling
B. Prevent the electron beam from spreading
C. Prevent oscillations
D. Prevent spurious oscillations

Back 559

B. Prevent the electron beam from spreading

Front 560

Prior to testing any RADAR system, the operator should first:
A. Check the system grounds
B. Assure the display unit is operating normally
C. Inform the airport control tower or ship's master
D. Assure that no personnel are in front of the antenna

Back 560

D. Assure that no personnel are in front of the antenna

Front 561

In the term "ARPA RADAR," ARPA is the acronym for which of the following?
A. Automatic RADAR Plotting Aid
B. Automatic RADAR Positioning Angle
C. American RADAR Programmers Association
D. Authorized RADAR Programmer and Administrator

Back 561

A. Automatic RADAR Plotting Aid

Front 562

Which of the following is NOT a precaution that should be taken to ensure the magnetron is not weakened:
A. Keep metal tools away from the magnet
B. Do not subject it to excessive heat
C. Keep the TR properly tuned
D. Do not subject it to shocks and blows

Back 562

C. Keep the TR properly tuned

Front 563

Exposure to microwave energy from RADAR or other electronic devices is limited by U.S. Health Department regulations to (blank) mW/centimeter.
A. 0.005
B. 5.0
C. 0.05
D. 0.5

Back 563

B. 5.0

Front 564

RADAR collision avoidance systems utilize inputs from each of the following except your ship's:
A. Gyrocompass
B. Navigation position receiver
C. Anemometer
D. Speed indicator

Back 564

C. Anemometer

Front 565

What is the orbiting altitude of the Iridium satellite communications system?
A. 22,184 miles
B. 11, 492 miles
C. 4,686 miles
D. 485 miles

Back 565

D. 485 miles

Front 566

What frequency band is used by the Iridium system for telephone and messaging?
A. 965 - 985 MHz
B. 1616 - 1626 MHz
C. 1855 - 1895 MHz
D. 2415 - 2435 MHz

Back 566

B. 1616 - 1626 MHz

Front 567

What services are provided by the Iridium system?
A. Analog voice and Data at 4.8 kbps
B. Digital voice and Data at 9.6 kbps
C. Digital voice and Data at 2.4 kbps
D. Analog voice and Data at 9.6 kbps

Back 567

C. Digital voice and Data at 2.4 kbps

Front 568

Which of the following statements about the Iridium system is true?
A. There are 48 spot beams per satellite with a footprint of 30 miles in diameter.
B. There are 48 satellites in orbit in 4 orbital planes.
C. The inclination of the orbital planes is 55 degrees.
D. The orbital period is approximately 85 minutes.

Back 568

A. There are 48 spot beams per satellite with a footprint of 30 miles in diameter.

Front 569

What is the main function of the COSPAS-SARSAT satellite system?
A. Monitor 121.5 MHz for voice distress calls.
B. Monitor 406 MHz for distress calls from EPIRBs.
C. Monitor 1635 MHz for coded distress calls.
D. Monitor 2197.5 kHz for hexadecimal coded DSC distress messages.

Back 569

B. Monitor 406 MHz for distress calls from EPIRBs.

Front 570

How does the COSPAS-SARSAT satellite system determine the position of a ship in distress?
A. By measuring the Doppler shift of the 406 MHz signal taken at several different positions in its orbit.
B. The EPIRB always transmits its position which is relayed by the satellite to the Local User Terminal.
C. It takes two different satellites to establish an accurate position.
D. None of the above.

Back 570

A. By measuring the Doppler shift of the 406 MHz signal taken at several different positions in its orbit.

Front 571

What is the orbital altitude of INMARSAT Satellites?
A. 16,436 miles
B. 22,177 miles
C. 20,450 miles
D. 26,435 miles

Back 571

B. 22,177 miles

Front 572

Which of the following describe the INMARSAT Satellite system?
A. AOR at 35˚ W, POR-E at 165˚ W, POR-W at 155˚ E and IOR at 56.5˚ E.
B. AOR-E at 25˚ W, AOR-W at 85˚ W, POR at 175˚ W and IOR at 56.5˚ E.
C. AOR-E at 15.5˚ W, AOR-W at 54˚ W, POR at 178˚ E and IOR at 64.5˚ E.
D. AOR at 40˚ W, POR at 178˚ W, IOR-E at 109˚ E and IOR-W at 46˚ E.

Back 572

C. AOR-E at 15.5˚ W, AOR-W at 54˚ W, POR at 178˚ E and IOR at 64.5˚ E.

Front 573

What are the directional characteristics of the INMARSAT-C SES antenna?
A. Highly directional parabolic antenna requiring stabilization.
B. Wide beam width in a cardioid pattern off the front of the antenna.
C. Very narrow beam width straight-up from the top of the antenna.
D. Omnidirectional.

Back 573

D. Omnidirectional.

Front 574

When engaging in voice communications via an INMARSAT-B terminal, what techniques are used?
A. CODECs are used to digitize the voice signal.
B. Noise-blanking must be selected by the operator.
C. The voice signal must be compressed to fit into the allowed bandwidth.
D. The voice signal must be expanded at the receiving terminal.

Back 574

A. CODECs are used to digitize the voice signal.

Front 575

Which of the folowing statements concerning INMARSAT geostationary satellites is true?
A. They are in a polar orbit, in order to provide true global coverage.
B. They are in an equatorial orbit, in order to provide true global coverage.
C. They provide coverage to vessels in nearly all of the worlds navigable waters.
D. Vessels sailing in equatorial water are able to use only one satellite, whereas other vessels are able to choose between at least two satellites.

Back 575

C. They provide coverage to vessels in nearly all of the worlds navigable waters.

Front 576

Which of the following conditions can render INMARSAT-B communications impossible?
A. An obstruction, such as a mast, causing disruption of the signal between the satellite and the SES antenna when the vessel is steering a certain course.
B. A satellite whose signal is on a low elevation, below the horizon.
C. Travel beyond the effective radius of the satellite.
D. All of the above.

Back 576

D. All of the above.

A. An obstruction, such as a mast, causing disruption of the signal between the satellite and the SES antenna when the vessel is steering a certain course.
B. A satellite whose signal is on a low elevation, below the horizon.
C. Travel beyond the effective radius of the satellite.

Front 577

What is the best description for the INMARSAT-C system?
A. It provides slow speed telex and voice service.
B. It is a store-and-forward system that provides routine and distress communications.
C. It is a real-time telex system.
D. It provides world-wide coverage.

Back 577

B. It is a store-and-forward system that provides routine and distress communications.

Front 578

The INMARSAT mini-M system is a:
A. Marine SONAR system.
B. Marine global satellite system.
C. Marine depth finder.
D. Satellite system utilizing spot beams to provide for small craft communications.

Back 578

D. Satellite system utilizing spot beams to provide for small craft communications.

Front 579

What statement best describes the INMARSAT-B services?
A. Voice at 16 kbps, Fax at 14.4 kbps and high-speed Data at 64/54.
B. Store and forward high speed data at 36/48 kbps.
C. Voice at 3 kHz, Fax at 9.6 kbps and Data at 4.8 kbps.
D. Service is available only in areas served by highly directional spot beam antennas.

Back 579

A. Voice at 16 kbps, Fax at 14.4 kbps and high-speed Data at 64/54.

Front 580

Which INMARSAT systems offer High Speed Data at 65/54 kbps?
A. C
B. B and C
C. Mini-M
D. B, M4 and Fleet

Back 580

D. B, M4 and Fleet

Front 581

When INMARSAT-B and INMARSAT-C terminals are compared:
A. INMARSAT-C antennas are small and omni-directional, while INMARSAT-B antennas are larger and directional.
B. INMARSAT-B antennas are bulkier but omni-directional, while INMARSAT-C antennas are smaller and parabolic, for aiming at the satellite.
C. INMARSAT-B antennas are parabolic and smaller for higher gain, while INMARSAT-C antennas are larger but omni-directional.
D. INMARSAT-C antennas are smaller but omni-directional, while INMARSAT-B antennas are parabolic for lower gain.

Back 581

A. INMARSAT-C antennas are small and omni-directional, while INMARSAT-B antennas are larger and directional.

Front 582

What services are provided by the INMARSAT-M service?
A. Data and Fax at 4.8 kbps plus e-mail.
B. Voice at 3 kHz, Fax at 9.6 kbps and Data at 4.8 kbps.
C. Voice at 6.2 kbps, Data at 2.4 kbps, Fax at 2.4 kbps and e-mail.
D. Data at 4.8 kbps and Fax at 9.6 kbps plus e-mail.

Back 582

C. Voice at 6.2 kbps, Data at 2.4 kbps, Fax at 2.4 kbps and e-mail.

Front 583

Global Positioning Service (GPS) satellite orbiting altitude is:
A. 4,686 miles
B. 24,184 miles
C. 12, 554 miles
D. 247 miles

Back 583

C. 12, 554 miles

Front 584

The GPS transmitted frequencies are:
A. 1626.5 MHz and 1644.5 MHz
B. 1227.6 MHz and 1575.4 MHz
C. 2245.4 and 2635.4 MHz
D. 946.2 MHz and 1226.6 MHz

Back 584

B. 1227.6 MHz and 1575.4 MHz

Front 585

How many GPS satellites are normally in operation?
A. 8
B. 18
C. 24
D. 36

Back 585

C. 24

Front 586

What best describes the GPS Satellites orbits?
A. They are in six orbital planes equally spaced and inclined about 55 degrees to the equator.
B. They are in four orbital planes spaced 90 degrees in a polar orbit.
C. They are in a geosynchronous orbit equally spaced around the equator.
D. They are in eight orbital planes at an altitude of approximately 1,000 miles.

Back 586

A. They are in six orbital planes equally spaced and inclined about 55 degrees to the equator.

Front 587

How many satellites must be received to provide complete position and time?
A. 1
B. 2
C. 3
D. 4

Back 587

D. 4

Front 588

What is DGPS?
A. Digital Ground Position System
B. A system to provide additional correction factors to improve position accuracy.
C. Correction signals transmitted by satellite.
D. A system for providing altitude corrections for aircraft.

Back 588

B. A system to provide additional correction factors to improve position accuracy.

Front 589

Compliance with MPE, or Maximum Permissible Exposure to RF levels (as defined in FCC Part 1, OET bulletin 65) for "controlled" environments, are averaged over (blank) minutes, while "uncontrolled" RF environments are averaged over (blank) minutes.
A. 6, 30
B. 30, 6
C. 1, 15
D. 15, 1

Back 589

A. 6, 30

Front 590

Sites having multiple transmitting antennas must include antennas with more than (blank) % of the maximum permissible power density exposure limit when evaluating RF site exposure.
A. Any
B. 5
C. 1
D. 12.5

Back 590

B. 5

Front 591

RF exposure from portable radio transceivers may be harmful to the eyes because:
A. Magnetic fields blur vision.
B. RF heating polarizes the eye lens.
C. The magnetic field may attract metal particles to the eye.
D. RF heating may cause cataracts.

Back 591

D. RF heating may cause cataracts.

Front 592

At what aggregate power level is an MPE (Maximum Permissible Exposure) study required?
A. 1000 watts ERP
B. 500 watts ERP
C. 100 watts ERP
D. Not required

Back 592

A. 1000 watts ERP

Front 593

Why must you never look directly into a fiber optic cable?
A. High power light waves can burn the skin surronding the eye.
B. An active fiber signal may burn the retina and infra-red light cannot be seen.
C. The end is easy to break.
D. The signal is red and you can see iyt.

Back 593

B. An active fiber signal may burn the retina and infra-red light cannot be seen.

Front 594

If the MPE (Maximum Permissible Exposure) power is present, how often must the personnel accessing the affected area be trained and certified?
A. Weekly
B. Monthly
C. Yearly
D. Not at all

Back 594

C. Yearly

Front 595

What device can protect a transmitting station from a direct lightning hit?
A. Lightning protector
B. Grounded cabinet
C. Short lead in
D. There is no device to protect a station from a direct hit from lightning

Back 595

D. There is no device to protect a station from a direct hit from lightning

Front 596

What is the purpose of not putting sharp corners on the ground leads within a building?
A. No reason
B. It is easier to install
C. Lightning will jump off of the ground lead because it is not able to make sharp bends.
D. Ground leads should always be made to look good in an installation, including the use of sharp bends in the corners.

Back 596

C. Lightning will jump off of the ground lead because it is not able to make sharp bends.

Front 597

Should you use a power drill without eye protection?
A. Yes
B. No
C. It's ok as long as you keep your face away from the drill bit.
D. Only in an extreme emergency.

Back 597

B. No

Front 598

What class of fire is one that is caused by an electrical short circuit and what is the preferred substance used to extinguish that type of fire?
A. FE28
B. FE29
C. FE30
D. FE31

Back 598

C. FE30

Front 599

Do short-stub lightning protectors work at all frequencies?
A. Yes.
B. No, the short also kills the radio signals.
C. No, the short enhances the radio signal at the tuned band.
D. No, only at the tuned frequency band.

Back 599

D. No, only at the tuned frequency band.

Front 600

What is a GFI electrical socket used for?
A. To prevent electrical shock by sensing ground path current and shutting the circuit down.
B. As a gold plated socket.
C. To prevent children from sticking objects in the socket.
D. To increase the current capacity of the socket.

Back 600

A. To prevent electrical shock by sensing ground path current and shutting the circuit down.