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RE: 12au7 to 12bh7

Posted by Jim McShane on June 21, 2017 at 15:02:42:
-Lastly, measure the power transformer's temperatures before and after the installation of the 12BH7s. I'm not sure what the maximum rating would be (especially for your case), but from my understanding anything hot to the touch is a no-no. Warm is fine, but not on the verge of burning.
Not true! Even cheap trafos are rated for much higher than the 130 F or so temps that makes it too hot to leave your hand on more than a few seconds.
Your post had a lot of good advice - but a power trafo at 150 F is just loafing.
Edited to fix typo...