[AMRadio] New Transmitter

Jack Schmidling jack at schmidling.com
Mon Nov 27 10:35:14 EST 2006

Jim Wilhite wrote:
> In my 1964 handbook there is a One-Band Kilowarr Amplifier that uses a 
> pair of 813s.  It is grid input and would be easy to modulate using 811s 
> or 572Bs.

That brings up something that is confusing to me.  I have been reviewing 
specs to get familiar with the more popular tubes out there as they were 
just numbers to drool over back when I was homebrewing.  I never got 
beyond 807's.

Anyway, I looked into 872's because that is what is in my SB200 and was 
surprised to find that the plate dissipation is considerably higher than 
an 813.

So, why would one not modulate 872's with 813's?

I guess I should forget about the higher voltages.  Too many senior 
moments these days.


p.s.  The D104 works great with the new Mouser cartridge.

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