G7 – PRACTICAL CIRCUITS Flashcards
G7A01 (B) What useful feature does a power supply bleeder resistor provide?
B. It ensures that the filter capacitors are discharged when power is removed
G7A02 (D) Which of the following components are used in a power supply filter network?
D. Capacitors and inductors
G7A03 (D) What is the peak-inverse-voltage across the rectifiers in a full-wave bridge power supply?
D. Equal to the normal peak output voltage of the power supply
G7A04 (D) What is the peak-inverse-voltage across the rectifier in a half-wave power supply?
D. Two times the normal peak output voltage of the power supply
G7A05 (B) What portion of the AC cycle is converted to DC by a half-wave rectifier?
B. 180 degrees
G7A06 (D) What portion of the AC cycle is converted to DC by a full-wave rectifier?
D. 360 degrees
G7A07 (A) What is the output waveform of an unfiltered full-wave rectifier connected to a resistive load?
A. A series of DC pulses at twice the frequency of the AC input
G7A08(C) Which of the following is an advantage of a switchmode power supply as compared to a linear power supply?
C. High frequency operation allows the use of smaller components
G7A09 (C) Which symbol in figure G7-1 represents a field effect transistor?
C. Symbol 1
G7A10 (D) Which symbol in figure G7-1 represents a Zener diode?
D. Symbol 5
G7A11 (B) Which symbol in figure G7-1 represents an NPN junction transistor?
B. Symbol 2
G7A12 (C) Which symbol in Figure G7-1 represents a multiple-winding transformer?
C. Symbol 6
G7A13 (A) Which symbol in Figure G7-1 represents a tapped inductor?
A. Symbol 7
G7B01 (A)
Complex digital circuitry can often be replaced by what type of integrated circuit?
A. Microcontroller
G7B02 (A)
Which of the following is an advantage of using the binary system when processing digital signals?
A. Binary “ones” and “zeros” are easy to represent by an “on” or “off” state
G7B03 (B)
Which of the following describes the function of a two input AND gate?
B. Output is high only when both inputs are high
G7B04 (C)
Which of the following describes the function of a two input NOR gate?
C. Output is low when either or both inputs are high
G7B05 (C)
How many states does a 3-bit binary counter have?
C. 8
G7B06 (A)
What is a shift register?
A. A clocked array of circuits that passes data in steps along the array
G7B07 (D)
What are the basic components of virtually all sine wave oscillators?
D. A filter and an amplifier operating in a feedback loop
G7B08 (B)
How is the efficiency of an RF power amplifier determined?
B. Divide the RF output power by the DC input power
G7B09 (C)
What determines the frequency of an LC oscillator?
C. The inductance and capacitance in the tank circuit
G7B10 (D)
Which of the following is a characteristic of a Class A amplifier?
D. Low distortion
G7B11 (B)
For which of the following modes is a Class C power stage appropriate for amplifying a modulated signal?
B. CW
G7B12 (D)
Which of these classes of amplifiers has the highest efficiency?
D. Class C
G7B13 (B)
What is the reason for neutralizing the final amplifier stage of a transmitter?
B. To eliminate self-oscillations
G7B14 (B)
Which of the following describes a linear amplifier?
B. An amplifier in which the output preserves the input waveform
G7C01 (B)
Which of the following is used to process signals from the balanced modulator then send them to the mixer in some single sideband phone transmitters?
B. Filter
G7C02 (D)
Which circuit is used to combine signals from the carrier oscillator and speech amplifier then send the result to the filter in some single sideband phone transmitters?
D. Balanced modulator
G7C03 (C)
What circuit is used to process signals from the RF amplifier and local oscillator then send the result to the IF filter in a superheterodyne receiver?
C. Mixer
G7C04 (D)
What circuit is used to combine signals from the IF amplifier and BFO and send the result to the AF amplifier in some single sideband receivers?
D. Product detector
G7C05 (D)
Which of the following is an advantage of a transceiver controlled by a direct digital synthesizer (DDS)?
D. Variable frequency with the stability of a crystal oscillator
G7C06 (B)
What should be the impedance of a low-pass filter as compared to the impedance of the transmission line into which it is inserted?
B. About the same
G7C07 (C)
What is the simplest combination of stages that implement a superheterodyne receiver?
C. HF oscillator, mixer, detector
G7C08 (D)
What type of circuit is used in many FM receivers to convert signals coming from the IF amplifier to audio?
D. Discriminator
G7C09 (D)
Which of the following is needed for a Digital Signal Processor IF filter?
A. An analog to digital converter
B. A digital to analog converter
C. A digital processor chip
D. All of the these choices are correct
G7C10 (B)
How is Digital Signal Processor filtering accomplished?
B. By converting the signal from analog to digital and using digital processing
G7C11 (A)
What is meant by the term “software defined radio” (SDR)?
A. A radio in which most major signal processing functions are performed by software
