HUNT CUTOFF DETECTOR P/O MODULE A4200.

TM 11-5820-670-30

1-44. HUNT CUTOFF DETECTOR P/O MODULE A4200.

EL1AT117

Frequency modulated 11.5 MHz if. from module A4100 enters the hunt cutoff detector from the fourth

if. amp. The hunt cutoff detector rectifies the signal and applies a dc bias voltage to hunt generator

A8400. 11.5 MHz if. is also coupled to the fifth if. amp and then proceeds through the receiver

The dc bias voltage is applied to the hunt generator only if 11.5 MHz if. is present at the fourth if. amp

output. If the master oscillator shifts frequency substantially, the if. signal at the hunt cutoff detector

will be lost and the dc bias voltage supplied to the hunt generator will be removed. Removal of the dc

bias voltage activates the hunt generator which supplies an error voltage to the oscillator circuits to

correct the operating frequency. Presence of the 11.5 MHz if. signal causes the hunt cutoff detector

to bias off the hunt generator. For a discussion of the master oscillator frequency control loop, see

The hunt cutoff detector operates in transmit and homing modes. For a discussion of the detector

operating in homing mode, see paragraph 1-50.

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