I need to replace the power transformer in a Truetone D 727. I do not know what the secondary voltage needs to be. The radio uses an 80 tube for the rectifier, two 42 tubes for the audio amp, and one 8 mfd and one 16 mfd cap for the filters. If you wish to view the schematic, it's the same as a Detrola model 175. Any form of help or advice is appreciated!

Hello Friend.

Half excuse my English scratched. A practical way exists for you to calculate its transformers. See: A valve 80, it can supply (or to rectify), up to 2 amperes. They are 5 Volts on 2 amperes; 6,3 volts on (there you add all the valves of 6,3 volts and it adds the currents of the same ones). For example: You said that he uses 2 valves 42, then I suppose that works with a valve pré-amplificadora and another as phase inversora. They are only there 4 Valves, being the ones that of exit, they consume 0,7A, and more two with 0,3A. Does it use magic eye? He/she/it to use it disappears more 0,3 and also, for each valve the more than he has. There you will have the current total of the 6,3Volts. If its radio uses field reel in the high speaker, use 2 X350Volts for 150 to for 180mA. Not to use field reel, use 2X 275 Volts for 150 to 180 MA. That variation exists, therefore it depends of the he/she enters iron of the original transformer. He/she grieves we be far, because I would adore to re-do this transformer for you. I hope to have helped.
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