Login or Register for FREE!
Login or Register for FREE!
Subel. B
6 questions
Subelement B

Transmitting Systems

Section 13

Modulation

In a solid-state RADAR modulator, the duration of the transmitted pulse is determined by:

  • The thyratron.
  • The magnetron voltage.
  • Correct Answer
    The pulse forming network.
  • The trigger pulse.
This question does not yet have an explanation! Register to add one

Tags: none

The modulation frequency of most RADAR systems is between:

  • Correct Answer
    60 and 500 Hz.
  • 3000 and 6000 Hz.
  • 1500 and 7500 Hz.
  • 1000 and 3000 Hz.
This question does not yet have an explanation! Register to add one

Tags: none

A shipboard RADAR uses a PFN driving a magnetron cathode through a step-up transformer. This results in which type of modulation?

  • Frequency modulation.
  • Amplitude modulation.
  • Continuous Wave (CW) modulation.
  • Correct Answer
    Pulse modulation.

The PFN - Pulse-Forming Network pulse-modulates the transmitting Magnetron's output, so Answer D. is the right answer.

Last edited by jahman. Register to edit

Tags: none

In a pulse modulated magnetron what device determines the shape and width of the pulse?

  • Correct Answer
    Pulse Forming Network.
  • Thyratron.
  • LC parallel circuit.
  • Dimensions of the magnetron cavity.

The PFN - Pulse-Forming Network pulse-modulates the transmitting Magnetron's output, so Answer A. is the right answer.

Last edited by jahman. Register to edit

Tags: none

What device(s) may act as the modulator of a RADAR system?

  • Magnetron.
  • Klystron.
  • Video amplifier.
  • Correct Answer
    Thyratron or a silicon-controlled rectifier (SCR).

These are used to switch the transmitter's very high voltage (rf) ON & OFF in response to a control signal.

Thyratron's are the older Tube style, SCR (Silicon Controlled Rectifiers) are the more modern Solid State device, but they both do the same thing.

Turn ON/OFF or "Modulates the signal"

Last edited by powerjl. Register to edit

Tags: none

The purpose of a modulator in the transmitter section of a RADAR is to:

  • Improve bearing resolution.
  • Correct Answer
    Provide the correct waveform to the transmitter.
  • Prevent sea return.
  • Control magnetron power output.

"Correct wavefrom" means a wave pulse modulated (shaped) as the pulse generated by the PFN - Pulse-Forming Network, so Answer B. is he right answer.

Last edited by jahman. Register to edit

Tags: none

Go to 12 Go to 14
HamStudy.org™ is copyright 2024 Signal Stuff™, All rights reserved.
View Privacy Policy    |    Get help with HamStudy.org™