FCC Technician Exam Question Pool. Subelement 3AD. Amateur Radio Practice. 4 Questions. -------------------------------------------------- 3D 1.1 C Where should the Green wire in an AC line cord be attached in a power supply? A. To the fuse. B. To the "hot" side of the power switch. C. To the chassis. D. To the meter. 3D 1.2 D Where should the Black (or Red) wire in a three wire line cord be attached in a power supply? A. To the filter capacitor. B. To the DC ground. C. To the chassis. D. To the fuse. 3D 1.3 B Where should the White wire in a three wire line cord be attached in a power supply. A. To the fuse. B. To one side of the transformer's primary winding. C. To the Black wire. D. To the rectifier junction. 3D 1.4 B Why is the retaining screw in one terminal of a light socket made of brass, while the other one is silver colored? A. To prevent galvanic action. B. To indicate correct polarity. C. To better conduct current. D. To reduce skin effect. 3D 2.1 A How much electrical current flowing through the Human Body is usually fatal? A. As little as 100 milliamperes may be fatal. B. Approximately 10 amperes is required to be fatal. C. More than 20 amperes is needed to kill a human being. D. No amount of current will harm you. Voltages of over 2000 volts are always fatal, however. 3D 2.2 A What is the minimum voltage considered to be dangerous to humans? A. 30 volts. B. 100 volts. C. 1000 volts. D. 2000 volts. 3D 2.3 C Where should the Main Power line switch for a High Voltage Power Supply be situated? A. Inside the cabinet, to interrupt power when the cabinet is opened. B. On the rear panel of the High Voltage Supply. C. Where it can be seen and reached easily. D. This supply should not be switch operated. 3D 2.5 A How much electrical current flowing through the Human Body is usually painful? A. As little as 50 milliamperes may be painful. B. Approximately 10 amperes is required to be painful. C. More than 20 amperes is needed to be painful to a human being. D. No amount of current will be painful. Voltages of over 2000 volts are always painful, however. 3D 5.2 A Where in the antenna transmission line should a Peak Reading Wattmeter be attached to determine the transmitter power output? A. At the transmitter output. B. At the antenna feedpoint. C. One Half wavelength from the antenna feedpoint. D. One Quarter wavelength from the transmitter output. 3D 5.3 B If a directional rf wattmeter indicates 90 Watts forward power and 10 Watts reflected power, what is the actual transmitter forward power? A. 10 watts. B. 80 watts. C. 90 watts. D. 100 watts. 3D 5.4 C If a directional rf wattmeter indicates 96 Watts forward power and 4 Watts reflected power, what is the actual transmitter forward power? A. 80 watts. B. 88 watts. C. 92 watts. D. 100 watts. 3D 7.1 D What is a MULTIMETER? A. An instrument capable of reading SWR and power. B. An instrument capable of reading resistance, capacitance and inductance. C. An instrument capable of reading resistance and reactance. D. An instrument capable of reading voltage, current and resistance. 3D 7.2 C How can the range of a voltmeter be extended? A. By adding resistance in series with the circuit under test. B. By adding resistance parallel to the circuit under test. C. By adding resistance in series with the meter. D. By adding resistance parallel to the meter. 3D 7.3 B How is a voltmeter typically connected to a circuit? A. In series with the circuit. B. In parallel with the circuit. C. In quadrature with the circuit. D. In phase with the circuit. 3D 7.4 D How can the range of an ammeter be extended? A. By adding resistance in series with the circuit under test. B. By adding resistance parallel to the circuit under test. C. By adding resistance in series with the meter. D. By adding resistance parallel to the meter. 3D 8.1 A What is a MARKER GENERATOR? A. A high stability oscillator that generates a series of reference signals at known frequency intervals. B. A low stability oscillator that "Sweeps" through a band of frequencies. C. An oscillator often used in aircraft to determine the craft's location relative the inner and outer markers at airports. D. A high stability oscillator whose output frequency and amplitude can be varied over a wide range. 3D 8.2 D What piece of test equipment provides a variable frequency signal which can be used to check the frequency responce of a curcuit? A. Frequency Counter. B. Distortion Meter. C. Deviation Meter. D. Signal Generator. 3D 8.3 D What type of circuit is used to inject a frequency calibration signal into a communications receiver? A. A product detector. B. A receiver incremental tuning circuit. C. A balanced modulator. D. A crystal calibrator. 3D 8.4 A How is a MARKER GENERATOR used? A. To calibrate the tuning dial on a receiver. many frequencies simultaneously. B. To calibrate the volume control on a receiver. C. To test the amplitude linearity of an SSB transmitter. D. To test the frequency deviation of an FM transmitter. 3D 8.5 D When adjusting a transmitter filter circuit, what device is connected to the transmitter output? A. Multimeter. B. Litz wires. C. Receiver. D. Dummy antenna. 3D 11.1 B What is a REFLECTOMETER? A. An instrument used to measure signals reflecter from the Ionosphere. B. An instrument used to measure Standing Wave Ratio. C. An instrument used to measure transmission line impedance. D. An instrument used to measure radiation resistance. 3D 11.2 A For best accuracy when adjusting the impedance match between an antenna and feedline, where should the match indicating device be inserted for best accuracy? A. At the antenna feedpoint. B. At the transmitter. C. At the midpoint of the feedline. D. Anywhere along the feedline. 3D 11.3 D What is the device that can indicate impedance mismatches in an antenna system? A. A field strength meter. B. A set of lecher wires. C. A wavemeter. D. A reflectometer. 3D 11.4 B What is a REFLECTOMETER? A. An instrument used to measure signals reflecter from the Ionosphere. B. An instrument used to measure Standing Wave Ratio. C. An instrument used to measure transmission line impedance. D. An instrument used to measure radiation resistance. D. An instrument used to measure radiation resistance. 3D 11.5 C Where should a reflectometer be inserted into a long antenna transmission line in order to obtain the most valid Standing Wave Ratio indication? A. At any Quarter Wavelength interval along the transmission line. B. At the receiver end. C. At the antenna end. D. At any even Half Wavelength interval along the transmission line. 3D 12.1 B What result might be expected when using a Speech Processor with an emission J3E transmitter? A. A lower plate-current reading. B. A less natural-sounding voice. C. A cooler operating power supply. D. Greater PEP output. 3D 14.1 B What is a TRANSMATCH? A. A device for varying the resonant frequency of an antenna. B. A device for varying the impedance presented to the transmitter. C. A device for varying the tuning rate of the transmitter. D. A device for varying the electrical length of an antenna. 3D 14.2 D What is BALANCED LINE? A. Feed line with one conductor connected to ground. B. Feed line with both conductors connected to ground to balance out harmonics. C. Feed line with the outer conductor connected to ground at even intervals. D. Feed line with neither conductor connected to ground. 3D 14.3 C What is an UNBALANCED LINE? A. Feed line with neither conductor connected to ground. B. Feed line with both conductors connected to ground to balance out harmonics. C. Feed line with one conductor connected to ground. D. Feed line with the outer conductor connected to ground at even intervals. 3D 14.4 A What is a BALUN? A. A device for using an unbalanced line to supply power to a balanced load, or vice versa. B. A device to match impedances between two coaxial lines. C. A device used to connect a microphone to a balanced modulator. D. A counterbalance used with an azimuth/elevation rotator system. 3D 14.5 D What is the purpose of an Antenna Matching Circuit? A. To measure the impedance of the antenna. B. To compare the radiation patterns of two antennas. C. To measure the SWR of an antenna. D. To match impedances within the antenna system. 3D 14.8 A How is a TRANSMATCH used? A. It is connected between a transmitter and an antenna system, and tuned for minimum SWR at the transmitter. B. It is connected betwen a transmitter and an antenna system and tuned for minimum SWR at the antenna. C. It is connected between a transmitter and an antenna system, and tuned for minimum impedance. D. It is connected between a transmitter and a dummy load, and tuned for maximum output power. 3D 16.1 B What is a DUMMY ANTENNA? A. An isotropic radiator. B. A nonradiating load for a transmitter. C. An antenna used as a reference for gain measurements. D. The image of an antenna, located below ground. 3D 16.2 B Of what material may a dummy antenna be made? A. A wire-wound resistor. B. A noninductive resistor. C. A diode and resistor combination. D. A coil and capacitor combination. 3D 16.3 B What station accessory is used in place of an antenna during transmitter tests so that no signal is radiated? A. A Transmatch. B. A dummy antenna. C. A low-pass filter. D. A decoupling resistor. 3D 16.4 A What is the purpose of a DUMMY ANTENNA? A. To allow off-the-air transmitter testing. B. To reduce output power for QRP operation. C. To give comparative signal reports. D. To allow Transmatch tuning without causing interfefence. 3D 16.5 A How many Watts should a dummy load for use with a 100 Watt emission J3E transmitter with 50 ohm output be able to dissipate? A. A minimum of 100 watts continuous. B. A minimum of 141 watts continuous. C. A minimum of 175 watts continuous. D. A minimum of 200 watts continuous. 3D 17.1 C What is an S-METER? A. A meter used to measure sideband suppression. B. A meter used to measure spurious emissions from a transmitter. C. A meter used to measure relative signal strength in a receiver. D. A meter used to measure solar flux. 3D 18.1 C For the most accurate readings of a transmitter output power, where should the RF Wattmeter be inserted? A. The wattmeter should be inserted and the output measured one-quarter wavelength from the antenna feedpoint. B. The wattmeter should be inserted and the output measured one-half wavelength from the antenna feedpoint. C. The wattmeter should be inserted and the output power measured at the transmitter antenna jack. D. The wattmeter should be inserted and the output power measured at the Transmatch output. 3D 18.2 B At what impedance are RF Wattmeters usually designed to operate? A. 25 Ohms. B. 50 Ohms. C. 100 Ohms. D. 300 Ohms. 3D 18.3 A What is a DIRECTIONAL WATTMETER? A. An instrument that measures forward or reflected power. B. An instrument that measures the directional pattern of an antenna. C. An instrument that measures the energy consumed by the transmitter. D. An instrument that measures thermal heating in a load resistor. -------------------------------------------------- End of Subelement 3AD.