6AQ5 is the audio output tube, so presumably about 5K primary
impedance and 8 ohm secondary, although I'm not picky on these
parameters.

What I am picky about is that the transformer mounting holes are on 2"
centers. Looking at the AES catalog I see 2.375" centers, and also
1.5" centers, but the 1.5" one sounds really really too dinky.

Any other places I should be looking? Cannibalizing an old AA5? Don't
know the impedance parameters of those but they can't be too far off,
can they?

AA5s usually used 50L6s or 50C5s, both of which use 2.5K output
transformers. Secondaries usually feeding 3.2 ohm speakers, so you
might be able to get by if you use an 8 ohm speaker. However, you will
take a significant loss of bass (low audio frequencies). But in a
communications radio, that may not be that important.

I could suggest the use of an L shaped metal bracket to mount the
transformer to, and to mount to the chassis, but that would look rather
ugly. You probably are concerned about the looks of the chassis, so
that's not really a viable option.

On Jun 5, 4:12 pm, robert casey wrote:
I could suggest the use of an L shaped metal bracket to mount the
transformer to, and to mount to the chassis, but that would look rather
ugly. You probably are concerned about the looks of the chassis, so
that's not really a viable option.

What I don't want to do is to have to put any new holes into the
already pretty crowded chassis. I could imagine putting a different-
sized transformer underneath on a bracket but there's not an infinite
amount of room. I'll see what I can fit, but most likely I'll order
the AA5 transformer from RadioDaze that others here have mentioned.

Looks of the chassis? The top of the copper plated chassis is corroded
to brown and black. Underneath it's very clean.

Tim.