HP (Hewlett-Packard) HP 85660B ユーザーズマニュアル

After being filtered, the IF signal is applied to common-emitter amplifier Q6 which has
adjustable gain. IF Gain adjustment 

 can be adjusted to provide from 5 

 to 20 

 of

gain. This is used to adjust the level of the IF signal to the proper level for comparison to the

 signal in the 

 YTO Phase Detector.

The IF signal is further amplified by output amplifier Q5 and 

 Gain is approximately

21 

 This provides the proper level signal to drive the 

 YTO Phase Detector.

2