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1965 JTM45 with EL34s: Dropping Resistors?

Trouserpress

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I'm looking at a picture of a most original JTM45 that's running on EL34s - but those aren't really a good match for the old RS transformers, right?. Between V4 and the board you can see 3 grey components (most likely resistors?) that might probably have been put in to take some high voltage stress off of the power tubes.
drop1.jpg
I'm no engineer and not quite sure if that would be a proper arrangement. Please take a look and tell me what you think. Thanks,
Frank
 

Creach

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I'm looking at a picture of a most original JTM45 that's running on EL34s - but those aren't really a good match for the old RS transformers, right?. Between V4 and the board you can see 3 grey components (most likely resistors?) that might probably have been put in to take some high voltage stress off of the power tubes.
View attachment 158666
I'm no engineer and not quite sure if that would be a proper arrangement. Please take a look and tell me what you think. Thanks,
Frank
Hello Frank,
It should be a 1K resistor going to V4, and from this 1K a 470R on V4 and a 470R on V5.
On your picture the 1K resistor was replaced by the grey resistors and the 2 x 470R was replaced by a wire.
Here is a schematic and a picture of a JTM45 (with kt66) from 1965 that i saw a few years ago.
 

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Trouserpress

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Thanks Creach, so the original 1k(2w) in series with 2x 470R(1w) have been replaced by 3 assumably sturdier grey resistors and 2 leads. I wonder what value these might be and if that’s really all you have to do to complete a KT66 to EL34 conversion….???
I would have to buy it to get some more information (I‘m interested in doing so).
 

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