Valvestate 8100 & 8080 PCB improvement


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Nov 12, 2022
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I'm wanting to do this to my 8100 and I'm just comparing the diagram to the under the board wiring saunatonttu did. (I'm not great with circuit diagrams at all.)

So the polarities should look like this when tacking this protection circuit on the back? View attachment 83989
Also I'm guessing R2 and C1 are both going to Pin 5 on IC1 and that's why the Diodes are going to them?
Signed up to see the images in this thread while working on my 8100, and can confirm you have the diodes correct here (and posting this in case anyone else winds up here looking for the answer).