The PHILCO Phorum
38-3 Speaker - Printable Version

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38-3 Speaker - gfehlman - 02-13-2026

What is an available audio output transformer that will work in place of the existing original transformer Philco 32-7754?


RE: 38-3 Speaker - morzh - 02-13-2026

You need 10 kOhm load.

If you know your voice coil impedance (or at least resistance) and the power reuqired, pick from 125 Hammond series.

https://www.hammfg.com/125.htm

Let's say you have 4 ohm. (I do not know what it is).
You need 2500 times that, which would make it 50 turns ratio.
The closest one then would be output leads 2 and 4.

https://www.hammfg.com/electronics/transformers/audio/125a-125e

125B would give you 5 Watts, 125C - 8W.

In any case, you will be able to match most speakers to most tubes in pushpul using 125.