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RE: Diodes unsoldering themselves

Posted by Palustris on December 29, 2020 at 08:54:18:
Back in the 1980s I modified my H-K Citation V with Zener screen grid regulators. I used 5W parts and had to regulate each of the 4 screens independently to stay within the 5W rating. So each Zener also had a 5W resistor in series. These were each attached beneath its respective pentode. They worked fine, but eventually the heat generated by the Zeners and the voltage dropping resistor along with all the rest of the heat within the chassis caused the solder holding the diode to the standoff to melt leaving just the mechanical connection intact.

I realized that this was a bad situation, so I triode connected the pentodes.