How many questions are in subelement G7?

The current pool contains 38 questions in subelement G7.

general pool

Subelement G7 question review

All 38 official questions with the exact winning phrase marked.

G7A01G7A

What is the function of a power supply bleeder resistor?

BIt discharges the filter capacitors when power is removed

Why this answer

The key fact is It discharges the filter capacitors when power is removed. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Capacitors store energy in an electric field.

P = E × I

G7A02G7A

Which of the following components are used in a power supply filter network?

CCapacitors and inductors

Why this answer

The key fact is Capacitors and inductors. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Capacitors store energy in an electric field.

P = E × I

G7A03G7A

Which type of rectifier circuit uses two diodes and a center-tapped transformer?

AFull-wave

G7A04G7A

What is characteristic of a half-wave rectifier in a power supply?

AOnly one diode is required

Why this answer

The key fact is Only one diode is required. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: A diode normally lets current favor one direction.

P = E × I

G7A05G7A

What portion of the AC cycle is converted to DC by a half-wave rectifier?

B180 degrees

G7A06G7A

What portion of the AC cycle is converted to DC by a full-wave rectifier?

D360 degrees

G7A07G7A

What is the output waveform of an unfiltered full-wave rectifier connected to a resistive load?

AA series of DC pulses at twice the frequency of the AC input

G7A08G7A

Which of the following is characteristic of a switchmode power supply as compared to a linear power supply?

CHigh-frequency operation allows the use of smaller components

Why this answer

The key fact is High-frequency operation allows the use of smaller components. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I

G7A09G7A

Which symbol in figure G7-1 represents a field effect transistor?

CSymbol 1

G7A10G7A

Which symbol in figure G7-1 represents a Zener diode?

DSymbol 5

G7A11G7A

Which symbol in figure G7-1 represents an NPN junction transistor?

BSymbol 2

G7A12G7A

Which symbol in Figure G7-1 represents a solid core transformer?

CSymbol 6

G7A13G7A

Which symbol in Figure G7-1 represents a tapped inductor?

ASymbol 7

G7B01G7B

What is the purpose of neutralizing an amplifier?

BTo eliminate self-oscillations

G7B02G7B

Which of these classes of amplifiers has the highest efficiency?

DClass C

G7B03G7B

Which of the following describes the function of a two-input AND gate?

BOutput is high only when both inputs are high

G7B04G7B

In a Class A amplifier, what percentage of the time does the amplifying device conduct?

A100%

G7B05G7B

How many states does a 3-bit binary counter have?

G7B06G7B

What is a shift register?

AA clocked array of circuits that passes data in steps along the array

G7B07G7B

Which of the following are basic components of a sine wave oscillator?

DA filter and an amplifier operating in a feedback loop

G7B08G7B

How is the efficiency of an RF power amplifier determined?

BDivide the RF output power by the DC input power

Why this answer

Use this action or method: Divide the RF output power by the DC input power. It is the choice that directly completes the job described in the question.

P = E × I

G7B09G7B

What determines the frequency of an LC oscillator?

CThe inductance and capacitance in the tank circuit

G7B10G7B

Which of the following describes a linear amplifier?

BAn amplifier in which the output preserves the input waveform

G7B11G7B

For which of the following modes is a Class C power stage appropriate for amplifying a modulated signal?

BFM

Why this answer

The key fact is FM. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I

G7C01G7C

What circuit is used to select one of the sidebands from a balanced modulator?

BFilter

G7C02G7C

What output is produced by a balanced modulator?

DDouble-sideband modulated RF

G7C03G7C

What is one reason to use an impedance matching transformer at a transmitter output?

BTo present the desired impedance to the transmitter and feed line

G7C04G7C

How is a product detector used?

DUsed in a single sideband receiver to extract the modulated signal

G7C05G7C

Which of the following is characteristic of a direct digital synthesizer (DDS)?

DVariable output frequency with the stability of a crystal oscillator

G7C06G7C

Which of the following is an advantage of a digital signal processing (DSP) filter compared to an analog filter?

AA wide range of filter bandwidths and shapes can be created

G7C07G7C

What term specifies a filter’s attenuation inside its passband?

AInsertion loss

G7C08G7C

Which parameter affects receiver sensitivity?

DAll these choices are correct

G7C09G7C

What is the phase difference between the I and Q RF signals that software-defined radio (SDR) equipment uses for modulation and demodulation?

B90 degrees

G7C10G7C

What is an advantage of using I-Q modulation with software-defined radios (SDRs)?

BAll types of modulation can be created with appropriate processing

G7C11G7C

Which of these functions is performed by software in a software-defined radio (SDR)?

DAll these choices are correct

G7C12G7C

What is the frequency above which a low-pass filter’s output power is less than half the input power?

CCutoff frequency

Why this answer

The key fact is Cutoff frequency. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I

G7C13G7C

What term specifies a filter’s maximum ability to reject signals outside its passband?

DUltimate rejection

G7C14G7C

The bandwidth of a band-pass filter is measured between what two frequencies?

AUpper and lower half-power