Re: The "Sussex" Homebrew Valve Tester.
That seems strange to me - is there any chance that you can hook up a scope to see what the current pulse looks like and measure it. Having a quick look at some fast blow 250mA fuses and their ratings I can't see how it can blow as they should withstand the current from the 4.7uF+220nF capacitors when they charge with a wide margin.
If anyone else has seen that behavior it would be good if you can leave a comment here. The small 4.7uF/400V capacitor is necessary so the LR8 doesn't start to oscillate, 220nF is to low for that.
How much of the rest of the circuit after the fuse was soldered?
/Martin
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Martin, Sweden
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