I'll take a very wild stab at it. From the RCA TT-4 handbook, the 833's at 3000VDC require 400V peak G-G volts, that is 242 V RMS. The drive is 20W. That makes the current 82 mA. That makes the impedance 2950 ohms G-G.

If you have an old output transformer such as a 6K CT to 0-4-8-16 ohm type, and were to connect the transformer's 16 ohm winding to the 8 ohm winding on the power amp, then the secondary would look like 3000 ohms, close enough.

You could also do a chinsel-cheeze method and use a dual-primary power transformer (120V each primary) set up for 240VCT, and with a secondary voltage of 12VAC. Use one with at least 5 amps rating on the 12v winding. Hook the 12VAC winding to the power amp's 8 ohm output. The series'd two 120V windings of the power transformer (240VCT) now looks like 3200 ohms, close enough. You might be surprised how good a power transformer can sound when operated far below its ratings.

From: Don Moore R Moore <[EMAIL PROTECTED]>
Subject: [AMRadio] Matching a 100 watt PA am to drive 833'S
To: [email protected]
Cc: [email protected]
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I have a older BC 1F series gates transmitter.  I would like to do away
with the 845 driver tubes and drive the 833's with a 100 watt PA amp. Does anybody have any Ideas what I would need to match the amp to the
driver transformer of the 833's.
Don Moore
W5FFK

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