Although I read, and generally limit myself to posting, it seems that their
are some people who wonder what the DAF will do....
The DAF circuit was used in the CB world for quite a long time in a line of
"modulator" amplifiers... They would do a strange thing to an AM signal....
Something like this..
Since their is no screen voltage at idle, and very little gain, when an AM
carrier is applied, the carrier power is almost fed through unamplified
(that is, the amp is running at such low gain,... The 4 watt carrier might
jump up to 5 or 6 watts of carrier out of the amp).
However, when the positive shift from the modulated waveform was applied,
due to it being rectified and applied to the screen and the gain of the tube
going "seemingly" through the roof, the wattmeter would jump wildly up...
Increasing the "apparent" modulation of the AM signal....
This made for one hell of a loud AM signal, as well as a broadband, near
spark gap signal
IOW,
Apply a 4 watt carrier, you get 4 watts of carrier output.
Apply a 100 percent modulated carrier (16 PEP watts), you would see nearly
300 watts PEP output.
This (AFAIK) is due entirely to the gain of the tube being varied by the
rectified portion of the driving signal being applied to the screen.
The grid bias voltage was chosen to keep the "resting" (AM carrier power)
where you wanted it.
You can also think of this as "screen RE-modulated AM".
Interestingly enough, if you piledrove it on SSB, people couldn't tell you
where using an amplifier, other than the fact that you had a larger
signal... However, on adjacent channels, I seem to recall that their was
quite a bit of "residual" signal.
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