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Bias in SSB operation is set to 25ma for the driver and 50ma for the final. (per factory service manual) This should be Class A with 12 volts on the collectors. In AM mode the voltage regulator drops the collector voltage by about half. Assuming that lowers the bias to Class C?

I just know high level modulation schemes are class C or lower. Without getting too technical (on stuff that I really dont know much about) The AM carrier is enough to essentially "turn on" the transistor or tube. With a carrier the waveform can be replicated at a full 360* cycle. So no bias or higher class bias isn't needed, increasing the efficiency of the AM modulator.

I was told by someone who knows a lot more than I do, that high level modulation scheme cannot be higher than class C for the modulated amp.

[QUOTE="JoeDirt, post: 566477, member: 8425"] Bias in SSB operation is set to 25ma for the driver and 50ma for the final. (per factory service manual) This should be Class A with 12 volts on the collectors. In AM mode the voltage regulator drops the collector voltage by about half. Assuming that lowers the bias to Class C? I just know high level modulation schemes are class C or lower. Without getting too technical (on stuff that I really dont know much about) The AM carrier is enough to essentially "turn on" the transistor or tube. With a carrier the waveform can be replicated at a full 360* cycle. So no bias or higher class bias isn't needed, increasing the efficiency of the AM modulator. I was told by someone who knows a lot more than I do, that high level modulation scheme cannot be higher than class C for the modulated amp. [/QUOTE]

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