Hypothetical question about JMP Output trannies...

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donzoid
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Hypothetical question about JMP Output trannies...

Post by donzoid »

I have a hypothetical question.

Based on the output transformer (primary side), is it possible that a previous tech may have gotten the center tap and one leg reversed? Would the amp even work (without transformer failure) and if this were the case, wouldn't my ohmage readings be roughly half on one side vs the other (or at least significantly different)? Yeah, you've probably gotten strange - er questions, but I had to ask. At this point I trust my suppliers and knowledge base more than previous work. Now I'm on a mission to clean it all up...

For example: A Drake (replacement) OT in my 50 is wired with red as center tap, and the legs as brown and white. Ohmage measurements are very close at about 44 Ohms so this "seems" OK.

One of my 100 watters, with an original OT is wired with white as CT, and the red and brown leads are the legs. These are also pretty close Ohms at 15.6 and 16.5

Granted, they are different parts for different wattage...I guess my question is -- is it normal for the same company (Drake in this case) to color code the same three colors for different purposes?

Thanks in advance...all best
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ToneMerc
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Re: Hypothetical question about JMP Output trannies...

Post by ToneMerc »

donzoid wrote:.I guess my question is -- is it normal for the same company (Drake in this case) to color code the same three colors for different purposes?
Yes, IIRC Drake's are spread across 3 or so different primary CT colors and secondaries are spread across different color schemes too. Thus, you can't all the time assume that red is the primary center.

TM
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donzoid
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Re: Hypothetical question about JMP Output trannies...

Post by donzoid »

Great...Thanks TM!
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