Gotta issue.

Can't find a schematic or any specs for the M15-a amp...

Problem: Bad Power tranny.....need to replace, but don't know the values.
Obviously the primary is 120VAC... filiments are typically 5Volts

Can't order an off the shelf Tranny without more specifics, such as what the secondaries should put out in terms of voltages.

Any help? Anyone have numbers on this transformer?

Any suggestions will be appreciated. Already talked to TRIAD and MERCURY.

Regards, Louie7

OK. M15-A: one 15 inch Jensen Concert speaker. (Great speakers for clean and jangle; I use the Concert 12 for my guitar amp). Two 6L6 power tubes in the conventional push-pull circuit.

Back then, everyone got their amplifier designs, including Leo Fender and others, from the RCA tube book. And there weren't that many manufacturers of parts. I would suggest that if you can't find an actual part number to cross reference, that the same transformer as used in the analog Fender bass amp of the same era with a similar circuit would work.