> On the front top-left, but normally covered by the faceplate,
> is a diode/transister/round-thing that says in TINY TINY LETTERS
> "Bendix 2N1227 ??? 1012 D 4"
Paul, that really isn't enough information for me to identify the unit.
However, what you are looking at here is almost certainly the audio output
transistor, and a 2N1227 is a PNP type device, which would normally be found
in a positive ground configuration.
That's no guarantee, of course. And as I'm sure you know, hooking it up
backwards _may_ instantly destroy the radio. So please don't blame me if
you damage it.
You might try carefully removing the covers, and see if you can find any
original maker markings inside them. You could also carefully trace the
circuitry around that transistor and see where it goes. The case is the
collector of the transistor, and must be negative with respect to the
emitter for the transistor to work.
Most likely it will be connected to a transformer winding and the other side
of the winding will be connected to the power switch (plus possibly some
filtering). If so, the unit is certainly positive ground.
If the amplifier uses capacitive coupling to the speaker rather than
transformer, then the collector will be connected to power through a
relatively low value power resistor.
Randall
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