[Milsurplus] 803 circuits

[David Stinson]

I simplified the circuit of the AVT-12 transmitter:

http://home.netcom.com/~arc5/AVT12a.jpg

It uses the large format RCA crystals.
Don't know if your little HC-25s or FT-243s
will hold up. The RFCs are like the ones
used in ART-13s.
The 803 suppressor is modulated at 50 volts
through the secondary of the modulator output transformer.
That voltage is developed by taking it off the top of
a honking-big 750 Ohm, 75 Watt resistor in the B- lead.
Whatever they gained in a smaller mod transformer,
they wasted in those two big 75-watt dropping resistors
for the screen and modulator, not to mention the 
huge ones in the dynamotor chassis to divide down
to Osc. B+.  I still don't see the advantage
of running Kamikaze B+ just to burn it off 
in King Kong voltage dividers.
If I ever get a chance to put an 803-like rig on the air,
it will be a serious candidate 
for reduced B+ experimentation.  
I'm too old, clumsy and forgetful to be twiddling 
around 2000 volts. I've lived over many 
3 or 400 volt shocks, but 2000 volts is instant death.
No thanks.
73 Dave S.