THIRD IF AMPLIFIER, LIMITER AND DISCRIMINATOR A4200A

TM 11-5820-401-34-3/0967-LP-432-3060

THIRD IF AMPLIFIER, LIMITER AND DISCRIMINATOR A4200A - SILICON TRANSISTOR

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VERSION.

Silicon Transistor Q4201 provides the third stage of amplification in the A4200A module. However,

discrete fourth and fifth stages are not used as in the germanium A4200 version.

Integrated Circuit U4201 provides additional amplification, limiting, and then detection of the audio

intelIigence. The discriminator consists of a quadrature coil detector which makes alinement easier

than it is when a Travis-type discriminator is used.

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AUDIO AND SQUELCH PREAMPLIFIER A4300.

EL4GQ207

The discriminator in the A4200 demodulates both audio intelligence and the transmitted 150-Hz new

squelch signals. The Audio and Squelch Preamplifier A4300 subjects both these frequencies to

preliminary stages of amplification.

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