Re: The "Sussex" Homebrew Valve Tester.
I am not sure now but think the fuse was intact (because it was over sized, oops!). I have since found D3 4 & 5 were also blown.
I have replaced components and tested the HT supply again on no load, but the voltage is way too high, does this circuit need a dummy load resistor to test it successfully?
Also the zener diodes, zd1 - zd7 are getting warm, the voltage across the zener's is 304v
Mike
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