3.4 KiB
3.4 KiB
G7C – Transceiver design; filters; oscillators; digital signal processing (DSP)
- G7C01 (B)
What circuit is used to select one of the sidebands from a balanced modulator? #card
- A. Carrier oscillator
- B. Filter
- C. IF amplifier
- D. RF amplifier
- G7C02 (D)
What output is produced by a balanced modulator? #card
- A. Frequency modulated RF
- B. Audio with equalized frequency response
- C. Audio extracted from the modulation signal
- D. Double-sideband modulated RF
- G7C03 (B)
What is one reason to use an impedance matching transformer at a transmitter output? #card
- A. To minimize transmitter power output
- B. To present the desired impedance to the transmitter and feed line
- C. To reduce power supply ripple
- D. To minimize radiation resistance
- G7C04 (D)
How is a product detector used? #card
- A. Used in test gear to detect spurious mixing products
- B. Used in transmitter to perform frequency multiplication
- C. Used in an FM receiver to filter out unwanted sidebands
- D. Used in a single sideband receiver to extract the modulated signal
- G7C05 (D)
Which of the following is characteristic of a direct digital synthesizer (DDS)? #card
- A. Extremely narrow tuning range
- B. Relatively high-power output
- C. Pure sine wave output
- D. Variable output frequency with the stability of a crystal oscillator
- G7C06 (A)
Which of the following is an advantage of a digital signal processing (DSP) filter compared to an analog filter? #card
- A. A wide range of filter bandwidths and shapes can be created
- B. Fewer digital components are required
- C. Mixing products are greatly reduced
- D. The DSP filter is much more effective at VHF frequencies
- G7C07 (A)
What term specifies a filter’s attenuation inside its passband? #card
- A. Insertion loss
- B. Return loss
- C. Q
- D. Ultimate rejection
- G7C08 (D)
Which parameter affects receiver sensitivity? #card
- A. Input amplifier gain
- B. Demodulator stage bandwidth
- C. Input amplifier noise figure
- D. All these choices are correct
- G7C09 (B)
What is the phase difference between the I and Q RF signals that software-defined radio (SDR) equipment uses for modulation and demodulation? #card
- A. Zero
- B. 90 degrees
- C. 180 degrees
- D. 45 degrees
- G7C10 (B)
What is an advantage of using I-Q modulation with software-defined radios (SDRs)? #card
- A. The need for high resolution analog-to-digital converters is eliminated
- B. All types of modulation can be created with appropriate processing
- C. Minimum detectible signal level is reduced
- D. Automatic conversion of the signal from digital to analog
- G7C11 (D)
Which of these functions is performed by software in a software-defined radio (SDR)? #card
- A. Filtering
- B. Detection
- C. Modulation
- D. All these choices are correct
- G7C12 (C)
What is the frequency above which a low-pass filter’s output power is less than half the input power? #card
- A. Notch frequency
- B. Neper frequency
- C. Cutoff frequency
- D. Rolloff frequency
- G7C13 (D)
What term specifies a filter’s maximum ability to reject signals outside its passband? #card
- A. Notch depth
- B. Rolloff
- C. Insertion loss
- D. Ultimate rejection
- G7C14 (A)
The bandwidth of a band-pass filter is measured between what two frequencies? #card
- A. Upper and lower half-power
- B. Cutoff and rolloff
- C. Pole and zero
- D. Image and harmonic