THIRD, FOURTH, AND FIFTH IF. AMPLIFIER, LIMITER AND DISCRIMINATOR A4200.

TM 11-5820-670-30

1-29. THIRD, FOURTH, AND FIFTH IF. AMPLIFIER, LIMITER AND DISCRIMINATOR A4200.

THIRD, FOURTH, AND FIFTH IF. AMPLIFIERS

EL1AT105

The third, fourth, and fifth if. amplifiers provide additional gain necessary to drive the limiter.

LIMITER AND DISCRIMINATOR

The limiter receives if. from the fifth if. amplifier. The positive and negative peaks of the if. waveform

are clipped by the limiter to provide a constant amplitude signal to the discriminator.

The discriminator is a travis-type containing tuned resonant tanks. When properly alined, the output

is the modulating intelligence with no dc offset. Any residual if. is shunted to ground by an rf trap.

Audio intelligence from the discriminator is applied to audio and squelch preamplifier module A4300.

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