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Hammond Output Transformer Feedback Loop Workaround
Sourbone
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Posts: 63
Threads: 29
Joined: Feb 2010
City: Richland, Michigan
#1

03-07-2011, 03:33 PM
Hello,

I'm replacing a Philco output transformer on a 39-40. I'm wondering how to work with the center tap connection on the primary or where the center tap used to be as well the feedback center tap on the secondary. I did read an earlier post about taking the high side of the secondary for the feedback. I was little uncertain about going about it. Can anyone help me out. Thanks.
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Radioroslyn
Phorum Expert
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Posts: 7,285
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
#2

03-07-2011, 08:21 PM
The center tap on the primary side isn't going to do you any good for feedback as there is no audio present at that point just HV. The feedback loop will have to be connected to the secondary. I would just experiment with the different taps till you find something you like. I'm assuming that the transformer has a multi tap secondary. If it oscillates (squeals) reverse the connections. That's called positive regeneration what you want negative feedback or negative regeneration.
Good luck!
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
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