35T in speech amp

[Barrie]

For no logical reason (that I can think of) I'd like to use a pair of 35Ts in a relatively high powered speech amp to drive a pair of 450TH modulators.

With 1300 volts on the plates, the output transformer would have to have about a 10K primary.

The secondary should be 600 ohms.  Or, could it be about right to go into the grids of the 450THs?

Where would I find such a transformer?  I think I'd have to have it built.

I'm lost!

73, Barrie, W7ALW

[KB3DKS]

Barrie,
I happen to have the Mod deck from a Gates 5P. This used a pair of CX? 2500s
for modulators. The driver transformer is a UTC CG coffee can about the size of a CVM5 and was driven by a quad of 6550/EL34s.
I have no idea of the functionality of this and do not know if I can immediatly get to it in the storage but if I can find the schematic or if you can, then it might be worth a dig.
I doubt that the complete deck would be worth shipping, freight, it weighs in at least 75 lbs and 28"X24"X8" at least.
I could pull the driver off it and ship that? Have no idea if the deck power tranny is good. This one was the spare deck.

FWIW

Bill, KB3DKS in 1 Land

[KM1H]

How is this for logic:

The 450TH's need a PEAK of 40W at the grids. Figure on twice that to cover losses.

35T's at 1300V will do around 175W, isnt that just a wee bit overkill?

Suggestion: Drop the voltage down to 700-800V and use a regular 70V driver transformer where you wont have to worry about insulation breakdown. This will also get you down into a more normal (available) range of PP load as used by 807, 6146's, etc.

Carl
KM1H