Login or Register for FREE!
Subelement ZLD

The Radio Receiver

Section ZLD16

Receiver Block Diagrams

In the block diagram of the receiver shown, the "RF amplifier"

  • decreases random fluctuation noise
  • is a restoring filter amplifier
  • Correct Answer
    increases the incoming signal level
  • changes the signal frequency
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "mixer"

  • Correct Answer
    combines signals at two different frequencies to produce one at an intermediate frequency
  • combines sidebands to produce a stronger signal
  • discriminates against SSB and AM signals
  • inserts a carrier wave to produce a true FM signal
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the output frequency of the "oscillator" is

  • the same as that of the incoming received signal
  • the same as that of the IF frequency
  • Correct Answer
    different from both the incoming signal and IF frequencies
  • at a low audio frequency
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "filter" rejects

  • AM and RTTY signals
  • Correct Answer
    unwanted mixer outputs
  • noise bursts
  • broadcast band signals
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "IF amplifier" is an

  • isolation frequency amplifier
  • intelligence frequency amplifier
  • indeterminate frequency amplifier
  • Correct Answer
    intermediate frequency amplifier
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "product detector"

  • produces an 800 Hz beat note
  • separates CW and SSB signals
  • rejects AM signals
  • Correct Answer
    translates signals to audio frequencies
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "AF amplifier"

  • rejects AM and RTTY signals
  • Correct Answer
    amplifies audio frequency signals
  • has a very narrow passband
  • restores ambiance to the audio
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "BFO" stands for

  • bad frequency obscurer
  • basic frequency oscillator
  • Correct Answer
    beat frequency oscillator
  • band filter oscillator
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, most of the receiver gain is in the

  • RF amplifier
  • Correct Answer
    IF amplifier
  • AF amplifier
  • mixer

Correct answer: IF amplifier

In a superheterodyne receiver, most of the receiver’s gain is provided in the intermediate frequency (IF) amplifier stage. Operating at a fixed frequency allows high gain, stable amplification, and precise filtering without instability or tuning issues.

The RF amplifier provides only moderate gain, mainly to improve sensitivity and reduce noise and image responses. The audio amplifier increases signal level for the speaker or headphones, but it does not contribute to RF sensitivity. The mixer performs frequency conversion and typically has little or no gain.

  • RF amplifier provides limited gain and is primarily used for noise performance and front-end selectivity.
  • AF amplifier increases audio power for listening but does not improve RF signal sensitivity.
  • mixer mainly performs frequency conversion and does not provide significant gain.

Therefore, most of the receiver gain is in the IF amplifier.

Last edited by jim.carroll. Register to edit

Tags: none

In the block diagram of the receiver shown, the "RF amplifier"

  • decreases random fluctuation noise
  • masks strong noise
  • Correct Answer
    should produce little internal noise
  • changes the signal frequency
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "mixer"

  • Correct Answer
    changes the signal frequency
  • rejects SSB and CW signals
  • protects against receiver overload
  • limits the noise on the signal
This question does not yet have an explanation! Register to add one

Tags: none

In the receiver shown, when receiving a signal, the output frequency of the "oscillator" is

  • the same as that of the signal
  • the same as that of the IF amplifier
  • Correct Answer
    of constant amplitude and frequency
  • passed through the following filter
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the "limiter"

  • Correct Answer
    limits the signal to a constant amplitude
  • rejects SSB and CW signals
  • limits the frequency shift of the signal
  • limits the phase shift of the signal

The demodulator will usually be a "discriminator" and may even be of a "phase-lock-loop" variety. There will be a "limiter" before the descriminator to remove noise peaks and amplitude-changes before detection of the FM signal

Last edited by cmscouler. Register to edit

Tags: none

In the block diagram of the receiver shown, the "frequency demodulator" could be implemented with a

  • product detector
  • Correct Answer
    phase-locked loop
  • full-wave rectifier
  • low-pass filter

The demodulator will usually be a "discriminator" and may even be of a "phase-lock-loop" variety.

Last edited by cmscouler. Register to edit

Tags: none

In the block diagram of the receiver shown, the "AF amplifier"

  • amplifies stereo signals
  • Correct Answer
    amplifies speech frequencies
  • is an all frequency amplifier
  • must be fitted with a tone control
This question does not yet have an explanation! Register to add one

Tags: none

In this receiver, an audio frequency gain control would be associated with the block labelled

  • Correct Answer
    AF amplifier
  • frequency demodulator
  • speaker, phones
  • IF amplifier
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the selectivity would be set by the

  • AF amplifier
  • mixer
  • limiter
  • Correct Answer
    filter
This question does not yet have an explanation! Register to add one

Tags: none

In the FM communications receiver shown in the block diagram, the "filter" bandwidth is typically

  • 3 kHz
  • Correct Answer
    10 kHz
  • 64 kHz
  • 128 kHz
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, an automatic gain control (AGC) circuit would be associated with the

  • Speaker
  • Correct Answer
    IF amplifier
  • RF filter
  • Oscillator
This question does not yet have an explanation! Register to add one

Tags: none

In the block diagram of the receiver shown, the waveform produced by the "oscillator" would ideally be a

  • square wave
  • pulsed wave
  • Correct Answer
    sinewave
  • hybrid frequency wave
This question does not yet have an explanation! Register to add one

Tags: none

Go to ZLC15 Go to ZLD17