Subelement B: Transmitting Systems – 8 Key Topics – 8 Exam Questions— Topic 17: Timer - Trigger - Synchronizer Circuits
Question 8-17B6
Element 8 (RADAR)Unblanking pulses are produced by the timer circuit. Where are they sent?
Explanation
Unblanking pulses are precisely timed signals used to turn on the electron beam in a Cathode Ray Tube (CRT) during the active display sweep. This ensures the trace is visible only when intended, preventing unwanted retrace lines from appearing on the screen. Therefore, these pulses are sent directly to the **CRT** to control its display. The CRT uses the electron beam to draw waveforms or images on its fluorescent screen, making it the destination for signals that manage beam visibility.
Options A, B, and D are incorrect as they represent components involved in radio frequency signal processing within a receiver, not display control. IF amplifiers boost intermediate frequency signals, the mixer converts RF to IF, and the discriminator demodulates FM signals. None of these functions involve controlling an electron beam for display purposes.
Related Questions
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