I am currently repairing an AK Model 30.
I do not have the speaker that would have gone with it.
What do I do to put a low impedance speaker on it.
It looks like I would use an audio output transformer.
What transformer impedance would be required and what about the DC requirements.
Can I use a modern set of headphones with a 2000 ohm or higher impedance?

Hi Paul

Use a low impedance speaker with matching transformer having 5000 ohm impedance. (Exact value isn't critical.) You will have the best results when the 2nd Audio Amplifier is a 71A rather than 01A. If you use a 71A be sure negative grid bias is around -22 1/2 volts.

You can use 2000 ohm headphones but these radios have a lot of amplification. Signals will be loud.

Norm

: I am currently repairing an AK Model 30.
: I do not have the speaker that would have gone with it.
: What do I do to put a low impedance speaker on it.
: It looks like I would use an audio output transformer.
: What transformer impedance would be required and what about the DC requirements.
: Can I use a modern set of headphones with a 2000 ohm or higher impedance?