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THE AM BULLETIN BOARD => Technical Forum => Topic started by: Opcom on January 14, 2026, 02:54:22 AM



Title: Could anyone please ID this RCA 400W RF amp?
Post by: Opcom on January 14, 2026, 02:54:22 AM
This is maybe a senior moment, as it's been sitting on a shelf for several years, apparently put aside and then forgotten then buried as more urgent work had to get done.
 
I bought it off ebay and IIRC the seller said its frequwncy range was 54-88MHz. It says "class AB" on the two amplifier boards. I was able to look up "Band I" to find that it is indeed 54-88MHz in the USA (47-68MHz in the EU). Unfortunately, searching hasn't turned up these old part numbers or documents.
I don't know what model of transmitter it's from.

The RCA name plate says:
400 WATT AMPLIFIER
BAND I
MI-563161-1
SERIAL 2386110
CAMDEN, N.J.

Some data on the two main amp boards are:
69893
CODE CC
CLASS AB
3477904-2B
L/P 3729671
MI-563181-1

So basically there's an input splitter made of PCB material, the pair of push pull amps, and a combiner made pf PC board as well. Additionally, a control board and multimeter & switch are at the front. A large power socket, and a row of large pins that apparently take the bias. ground, and other voltages that are needed. There's a huge heat sink on the underside.
Transistors: four 372901-2, and two 3729474-4.

Does anyone know if this might work on 6 meters (even at reduced power), and the correct voltages for it, or has the manual for it, so at least I could test it without frying it?

Thanks in advance,

Patrick
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands