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Cards In This Set
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G8B01 (A)
What receiver stage combines a 14.250 MHz input signal with a 13.795 MHz oscillator signal to produce a 455 kHz intermediate frequency (IF) signal? A. Mixer |
G8B02 (B)
If a receiver mixes a 13.800 MHz VFO with a 14.255 MHz received signal to produce a 455 kHz intermediate frequency (IF) signal, what type of interference will a 13.345 MHz signal produce in the receiver? B. Image response |
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G8B03 (A)
What stage in a transmitter would change a 5.3 MHz input signal to 14.3 MHz? A. A mixer |
G8B04 (D)
What is the name of the stage in a VHF FM transmitter that selects a harmonic of an HF signal to reach the desired operating frequency? D. Multiplier |
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G8B05 (C)
Why isn't frequency modulated (FM) phone used below 29.5 MHz? C. The bandwidth would exceed FCC limits |
G8B06 (D)
What is the total bandwidth of an FM-phone transmission having a 5 kHz deviation and a 3 kHz modulating frequency? D. 16 kHz |
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G8B07 (B)
What is the frequency deviation for a 12.21-MHz reactance-modulated oscillator in a 5-kHz deviation, 146.52-MHz FM-phone transmitter? B. 416.7 Hz |
G8B08 (C)
How is frequency shift related to keying speed in an FSK signal? C. Greater keying speeds require greater frequency shifts |
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G8B09 (B)
What do RTTY, Morse code, PSK31 and packet communications have in common? B. They are digital modes |
G8B10 (B)
When transmitting a data mode signal, why is it important to know the duty cycle of the mode you are using? B. To prevent damage to your transmitter's final output stage |
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G8B11 (D)
What part of the 20 meter band is most commonly used for PSK31 operation? D. Below the RTTY segment, near 14.070 MHz |
G8B12 (A)
What is another term for the mixing of two RF signals? A. Heterodyning |
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G9A01 (A)
Which of the following factors help determine the characteristic impedance of a parallel conductor antenna feedline? A. The distance between the centers of the conductors and the radius of the conductors |
G9A02 (B)
What is the typical characteristic impedance of coaxial cables used for antenna feedlines at amateur stations? B. 50 and 75 ohms |
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G9A03 (D)
What is the characteristic impedance of flat ribbon TV type twin lead? D. 300 ohms |
G9A04 (C)
What is a common reason for the occurrence of reflected power at the point where a feedline connects to an antenna? C. A difference between feedline impedance and antenna feed point impedance |
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G9A05 (D)
What must be done to prevent standing waves on an antenna feedline? D. The antenna feed point impedance must be matched to the characteristic impedance of the feedline |
G9A06 (C)
Which of the following is a reason for using an inductively coupled matching network between the transmitter and parallel conductor feed line feeding an antenna? C. To match the unbalanced transmitter output to the balanced parallel conductor feedline |
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G9A07 (B)
How does the attenuation of coaxial cable change as the frequency of the signal it is carrying increases? B. It increases |
G9A08 (D)
In what values are RF feed line losses usually expressed? D. dB per 100 ft |
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G9A09 (A)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a non-reactive load having a 200-ohm impedance? A. 4:1 |
G9A10 (D)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a non-reactive load having a 10-ohm impedance? D. 5:1 |
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G9A11 (B)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a non-reactive load having a 50-ohm impedance? B. 1:1 |
G9A12 (A)
What would be the SWR if you feed a vertical antenna that has a 25-ohm feed-point impedance with 50-ohm coaxial cable? A. 2:1 |
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G9A13 (C)
What would be the SWR if you feed a folded dipole antenna that has a 300-ohm feed-point impedance with 50-ohm coaxial cable? C. 6:1 |
G9A14 (B)
If the SWR on an antenna feedline is 5 to 1, and a matching network at the transmitter end of the feedline is adjusted to 1 to 1 SWR, what is the resulting SWR on the feedline? B. 5 to 1 |
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G9B01 (B)
What is one disadvantage of a directly fed random-wire antenna? B. You may experience RF burns when touching metal objects in your station |
G9B02 (D)
What is an advantage of downward sloping radials on a ground-plane antenna? D. They can be adjusted to bring the feed-point impedance closer to 50 ohms |
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G9B03 (B)
What happens to the feed-point impedance of a ground-plane antenna when its radials are changed from horizontal to downward-sloping? B. It increases |
G9B04 (A)
What is the low angle azimuthal radiation pattern of an ideal half-wavelength dipole antenna installed 1/2 wavelength high and parallel to the earth? A. It is a figure-eight at right angles to the antenna |
