10-20-2020, 02:35 PM
I wouldn't loose any sleep over it.
The dc resistance doesn't mean a whole lot as a number to verify the the ac impedance of the primary. As for burning up something the worst that could (but unlikely) is that the primary could open up do to excessive current flow. This would have to do with the rating of the transformer and not the set itself. If there was a mismatch between the tube and transformer you would have low volume and distortion. The ratings for many of the tubes used in ac/dc sets are the same so a transformer that was used with a 50C5 could be used with a 50B5, 50L6, 35L6, 35C5, 35B5, 25B6, and 25L6 there probably a few more. Transformers from an ac set using tubes like 2A5, 47, 42, 41, 6F6, 6V6, and 6F6 aren't a good match as these tube have a higher plate load impedance.
OBTW to answer your question no. Just like wire wound resistors they don't drift like carbon counterparts.
The dc resistance doesn't mean a whole lot as a number to verify the the ac impedance of the primary. As for burning up something the worst that could (but unlikely) is that the primary could open up do to excessive current flow. This would have to do with the rating of the transformer and not the set itself. If there was a mismatch between the tube and transformer you would have low volume and distortion. The ratings for many of the tubes used in ac/dc sets are the same so a transformer that was used with a 50C5 could be used with a 50B5, 50L6, 35L6, 35C5, 35B5, 25B6, and 25L6 there probably a few more. Transformers from an ac set using tubes like 2A5, 47, 42, 41, 6F6, 6V6, and 6F6 aren't a good match as these tube have a higher plate load impedance.
OBTW to answer your question no. Just like wire wound resistors they don't drift like carbon counterparts.
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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