Extra Exam - E4B

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B

E4B01 Which of the following is a characteristic of a good harmonic frequency marker? / A. Wide tuning range / B. Frequency stability / C. Linear output amplifier / D. All of the above

B

E4B02 Which of the following factors most affects the accuracy of a frequency counter? / A. Input attenuator accuracy / B. Time base accuracy / C. Decade divider accuracy / D. Temperature coefficient of the logic

C

E4B03 What is an advantage of using a bridge circuit to measure impedance? / A. It provides an excellent match under all conditions / B. It is relatively immune to drift in the signal generator source / C. The measurement is based on obtaining a null in voltage, which can be done very precisely / D. It can display results directly in Smith chart format

C

E4B04 If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading? / A. 165.2 Hz / B. 14.652 kHz / C. 146.52 Hz / D. 1.4652 MHz

A

E4B05 If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading? / A. 14.652 Hz / B. 0.1 MHz / C. 1.4652 Hz / D. 1.4652 kHz

D

E4B06 If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading? / A. 146.52 Hz / B. 10 Hz / C. 146.52 kHz / D. 1465.20 Hz

D

E4B07 How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power? / A. 100 watts / B. 125 watts / C. 25 watts / D. 75 watts

A

E4B08 Which of the following is good practice when using an oscilloscope probe? / A. Keep the ground connection of the probe as short as possible / B. Never use a high impedance probe to measure a low impedance circuit / C. Never use a DC-coupled probe to measure an AC circuit / D. All of these choices are correct

C

E4B09 Which of the following is a characteristic of a good DC voltmeter? / A. High reluctance input / B. Low reluctance input / C. High impedance input / D. Low impedance input

D

E4B10 What is indicated if the current reading on an RF ammeter placed in series with the antenna feedline of a transmitter increases as the transmitter is tuned to resonance? / A. There is possibly a short to ground in the feedline / B. The transmitter is not properly neutralized / C. There is an impedance mismatch between the antenna and feedline / D. There is more power going into the antenna

B

E4B11 Which of the following describes a method to measure intermodulation distortion in an SSB transmitter? / A. Modulate the transmitter with two non-harmonically related radio frequencies and observe the RF output with a spectrum analyzer / B. Modulate the transmitter with two non-harmonically related audio frequencies and observe the RF output with a spectrum analyzer / C. Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a peak reading wattmeter / D. Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a logic analyzer

D

E4B12 How should a portable SWR analyzer be connected when measuring antenna resonance and feedpoint impedance? / A. Loosely couple the analyzer near the antenna base / B. Connect the analyzer via a high-impedance transformer to the antenna / C. Connect the antenna and a dummy load to the analyzer / D. Connect the antenna feed line directly to the analyzer's connector

A

E4B13 What is the significance of voltmeter sensitivity expressed in ohms per volt? / A. The full scale reading of the voltmeter multiplied by its ohms per volt rating will provide the input impedance of the voltmeter / B. When used as a galvanometer, the reading in volts multiplied by the ohms/volt will determine the power drawn by the device under test / C. When used as an ohmmeter, the reading in ohms divided by the ohms/volt will determine the voltage applied to the circuit / D. When used as an ammeter, the full scale reading in amps divided by ohms/volt will determine the size of shunt needed

A

E4B14 How is the compensation of an oscilloscope probe typically adjusted? / A. A square wave is observed and the probe is adjusted until the horizontal portions of the displayed wave is as nearly flat as possible / B. A high frequency sine wave is observed, and the probe is adjusted for maximum amplitude / C. A frequency standard is observed, and the probe is adjusted until the deflection time is accurate / D. A DC voltage standard is observed, and the probe is adjusted until the displayed voltage is accurate

B

E4B15 What happens if a dip-meter is too tightly coupled to a tuned circuit being checked? / A. Harmonics are generated / B. A less accurate reading results / C. Cross modulation occurs / D. Intermodulation distortion occurs

B

E4B16 Which of these factors limits the accuracy of a D'Arsonval-type meter? / A. Its magnetic flux density / B. Coil impedance / C. Deflection rate / D. Electromagnet current

C

E4B17 Which of the following can be used as a relative measurement of the Q for a series-tuned circuit? / A. The inductance to capacitance ratio / B. The frequency shift / C. The bandwidth of the circuit's frequency response / D. The resonant frequency of the circuit

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