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Hello Everyone,
I am having issues with a K-17 speaker. The output transformer was bad and I need to replace it. I'm having trouble crossing the 32-7078 transformer. I bought a Hammonds 125D universal push-pull, but and not sure how to wire it up. Anybody have experience with this and can point me in the right direction?
Thank You in advance.
Matt
Posts: 15,444
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City: Jackson, NJ
You have 10,000 kOhm to 1.11 Ohm transformer, which means you have the ratio of 95 of I:II windings. The impedance at 1.5 ohms should be 13,636 so the closest you get is by connecting your speaker between 3 and 4 of the secondary.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,248
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City: Roslyn Pa
Hmmmm
The push/pull triode connected 42's w/fixed bias p to p load is 6K sez my '40 RCA tube manual and spec on the original transformer is 5.9K. With that in mind I would go w/ 1 and 3. Rca sez it will make abt 10watts @ 2% distortion. Wired as penodes they will abt twice the audio power but almost triple the distortion.
YMMV
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
(This post was last modified: 11-21-2018, 11:52 AM by
Radioroslyn.)
Posts: 15,444
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Joined: Oct 2011
City: Jackson, NJ
I think you are right. I didn't look much at the output stage, it seems to be direct-biased triode connection (cathode biased triode is still 10K) which is 6K.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,248
Threads: 266
Joined: Dec 2009
City: Roslyn Pa
>I think you are right.
I try!
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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