Re: Yes, yet another home made valve tester.
Adrian,I think you've got the right idea, homebrew-wise. Testers like the AVO's have a sequence of continuity & insulation procedures before finally testing for Ia/Vg by twiddling bridge balancing pots which indicate mA/V on a handy dial. However, folk with a modest collection of valves can easily do these basic tests by using a multimeter & a megger. Then simply alter Vg by a fixed amount & read off the change in Ia. Bobs your Uncle. And, the bonus is - you're supplying the valve with proper working DC, just as it would experience in a radio or amp chassis. In fact, its been mooted several times over the years by Forum folk that a decent redundant amp chassis can make a good donor for a homebrew DC tester.
Hopefully, once virus restrictions are lifted, you'll be able to pop down the road to Golborne & cheaply acquire any additional bits & bobs at the next BVWS Swapmeet.
Audiophoolery - has a lot to answer for. Expensive ECC, KT**,EL, etc. valves. Plus the urge to cough up mega bucks for a "must have" CT160 or similar tester(then go & phook it by proding inside with snips/screwdrivers & soldering irons !).
Regards, David
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