Unrevealed Source wrote:
Looking for help on this one. Am I reading the schematic correctly -
265V across the 5U4 filament, and 268V across the plate?

You are interpreting it incorrectly.

The 268 volts you are seeing on each plate is 268 volts -AC- to ground; to
put it another way, you are looking at a transformer with a 268-0-268
volt secondary (or a transformer with a 536 volt *center-tapped* secondary).

The 265 volts you refer to is +265 volts -DC-, measured from the
filament (cathode) to ground. The voltage -across- the 5U4 filament is 5
volts AC, the filament voltage of a 5U4.

I also notice that the tap to the pilot lamps is not labeled,
although I know from the parts list that they are 6.3V.

Yes, this feeds 6.3 volts AC to the pilot lights and the filaments of
the other tubes.

Assuming that this radio is intended for use at (nominally) 115 VAC, you
will need a transformer with a 110-120 v primary, and the following
three secondaries: 500 volts center tapped (250-0-250), 6.3v and 5 v.

I'm looking to replace the fried transformer, but I'm a bit in over
my head with regard to what to replace it with or whether to have it
rewound.

Jeff

This is a fairly typical receiver transformer. Check the web site of
Antique Electronics Supply and Hammond Transformers. Look for one with
these approximate electrical characteristics and physical
characteristics that most closely match the existing one. Rewinding will
probably cost more than a new one.

By the very nature of your question, it indicates that you are a
beginner -- which is OK; we were all beginners at one time. Just be
careful; these voltages, if not fatal, can at least be harmful.

Needless to say, check the radio for other faults so as not to toast the
replacement transformer.

Merry Christmas and good luck!