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Atwater Kent model 20 Big Box
#39

Have a question to throw out there about the audio transformers in this radio. I have a copy from an A-K data sheet, page 8-1. It does verify that both audio transformers should have the identical primary and secondary resistance. Primary 1700 ohms, secondary 3250 ohms. The data sheet is for a Model-20 #7570.
They next state the same audio transformer is used in the model-20 # 4640, (what I have). They state for radio model 20 # 4640 transformer part# 7661 is used in both the 1st and 2nd stages.

They also state that the transformer for the radio 20 model# 4640 is part# 7661.
The transformer for radio 20 model #7570 is part # 4779.

They go on to say even though each model has a different transformer part numbers, they are the same audio transformer.

So... all that as a prelude to my question.
Can two different transformers with the same primary and secondary resistance 1700/3250 ohms have a different turns ratio if one of them was wound with a larger diameter wire?

Feel free to respond in a manner that lets me know I'm being dense. Just trying to get a handle on having two transformers that match the factory data sheet resistance wise. But may be incorrect ratio wise. It would be nice to have some clarification before I go to the trouble of installing them. 

Like any newby, I might have my jock strap on backwards and don't even know it yet.


Messages In This Thread
Atwater Kent model 20 Big Box - by TTech - 04-18-2021, 05:49 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-18-2021, 05:53 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-18-2021, 06:56 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-18-2021, 09:56 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-19-2021, 12:51 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-19-2021, 10:14 AM
RE: Atwater Kent model 20 Big Box - by Chas - 04-19-2021, 11:46 AM
RE: Atwater Kent model 20 Big Box - by Eliot Ness - 04-19-2021, 01:31 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-19-2021, 05:59 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-19-2021, 07:47 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-19-2021, 08:52 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-20-2021, 09:47 AM
RE: Atwater Kent model 20 Big Box - by Chas - 04-20-2021, 11:28 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-20-2021, 12:15 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-20-2021, 02:29 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-21-2021, 08:19 AM
RE: Atwater Kent model 20 Big Box - by Chas - 04-21-2021, 10:54 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-21-2021, 01:01 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-21-2021, 11:13 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-22-2021, 04:45 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-22-2021, 05:30 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-23-2021, 08:18 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-23-2021, 05:28 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-24-2021, 09:39 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-24-2021, 11:03 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-25-2021, 10:52 AM
RE: Atwater Kent model 20 Big Box - by Chas - 04-25-2021, 11:20 AM
RE: Atwater Kent model 20 Big Box - by TTech - 04-25-2021, 12:51 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-25-2021, 04:59 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-26-2021, 05:18 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-29-2021, 01:38 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-29-2021, 05:23 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-29-2021, 06:01 PM
RE: Atwater Kent model 20 Big Box - by Chas - 04-29-2021, 06:10 PM
RE: Atwater Kent model 20 Big Box - by TTech - 04-29-2021, 06:41 PM
RE: Atwater Kent model 20 Big Box - by Phlogiston - 05-01-2021, 04:15 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-01-2021, 08:18 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-02-2021, 02:02 PM
RE: Atwater Kent model 20 Big Box - by Phlogiston - 05-02-2021, 05:17 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-03-2021, 02:35 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-04-2021, 03:47 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-04-2021, 06:26 PM
RE: Atwater Kent model 20 Big Box - by Chas - 05-06-2021, 12:05 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-07-2021, 09:34 AM
RE: Atwater Kent model 20 Big Box - by TTech - 05-07-2021, 09:58 AM
RE: Atwater Kent model 20 Big Box - by Chas - 05-07-2021, 10:50 AM
RE: Atwater Kent model 20 Big Box - by TTech - 05-07-2021, 12:46 PM
RE: Atwater Kent model 20 Big Box - by Chas - 05-07-2021, 01:01 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-12-2021, 09:59 AM
RE: Atwater Kent model 20 Big Box - by admin - 05-12-2021, 10:26 AM
RE: Atwater Kent model 20 Big Box - by Phlogiston - 05-12-2021, 06:18 PM
RE: Atwater Kent model 20 Big Box - by TTech - 05-12-2021, 09:49 PM
RE: Atwater Kent model 20 Big Box - by Chas - 05-14-2021, 12:13 PM
RE: Atwater Kent model 20 Big Box - by OZ4 - 05-17-2021, 12:57 PM



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