Re: Introduction & Tube 833A

Welcome Janne,
There are others on the list who can tell you much more about tube coils than
I can. I can give you specs for the 833A which is a transmitting triode 
capable of handling
2 kW of input power with forced-air cooling. At higher power levels you can 
expect to
see a cheerfull red glow on the plate. It is an excellent tube for a VTTC. 
There is a 833C
with a big thick graphite plate. Any time you spot a triode with a graphite 
plate you should grab it. The connections to the 833 are apparent from just 
looking at it. Finned (no pun)
heat radiating connectors are needed at the higher power levels. You can make 
them on a lathe or scrounge around for them.

>From the RCA Transmitting Tube Manual:

Fil V.................10V
Fil current.......10A

For intermittent service (short bursts to the TC):

all max ratings
DC plate V................4000V
DC plate current......  500mA
plate input.................1800W
plate diss..................  450W

The tube has a thoriated tungsten filament that needs to be operated as rated.
The only thing that gets better care around here is my dog. For long filament
life, a variac is a must. With no plate voltage applied, I always heat the 
filaments of my
high power tubes very slowly and I never dump the full voltage on a cold 
Also, I turn off the plate voltage so I can slowly cool-down the hot 

Play safely,
Ralph Zekelman