[Wayne Spackman]

Recently restored the audio section of an RCA 7Q51 5-band radio (Canadian mfg). Runs ok but the B+ measures 275 volts. Schematic says it should be 195. Transformer runs very very hot.
The schematic shows a switch on the primary for 120/240 volts but this model does not have the switch and only one pair of leads. Could a partial short in the primary cause this or am I missing something altogether?

[Sterling Spurrell]

Not really experienced myself but wondering if all caps have been done and all resistors checked?

[John Greenland]

Hi Wayne,

This does not appear to be the proper transformer for this radio.
This particular Hammond transformer has a 300 volt per side secondary.
The drawing shows only a transformer with 250 volts per side.
That is why your voltages are way off .

The wattage of the Hammond is high enough at 95 VA as your radio is rated around 60.
The fact the transformer is running hot, may be due to the high voltages.
Hope this helps

John G. VO1 CAT

[Author]

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