Re: VTTC grid leak

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Mddeming-at-aol-dot-com 

In a message dated 9/1/04 6:18:58 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:
As this circuit provides automatic level/bias control, I now
understand, why it is so difficult to amplitude modulate it. The
modulator tries to change the amplitude of the signal and the
oscillator tries to keep it constant.

Cheers,

Herwig

Hi Herwig,
     This is precisely why essentially all AM transmitters modulate in an 
amplifier stage and leave the oscillator isolated and stable. A good 
discussion of both oscillator stability and modulation problems may be 
found in "Fundamentals of Vacuum tubes" by A. V. Eastman, McGraw Hill, NY 
1941. It also has many specific references to now-obscure I.R.E Proceedings 
papers from the 1920s and '30s.

Hope this helps,

Matt D.