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Old 3rd Jul 2022, 6:50 pm   #34
high_vacuum_house
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Join Date: May 2003
Location: Belper Derbyshire
Posts: 1,910
Default Re: Faulty valves - Scrap or keep?

I have a few dud valves which I keep for messing around with on a rainy day. I made a couple of those valve component displays that Mullard made with the grids, cathode ECT. carefully glued to a back board.

I have a NOS EABC80 which the pip got broken off after an unlucky accident I intend to do the same with sometime

I did a nasty experiment to an EF80 that was a well baked pull from an old telly just to see what a small signal valve could take. With the heater lit correctly I connected a big high voltage power supply between anode and cathode without any current limiting I think I got nearly 500mA at over 400 volts before the cathode strip parted from the cathode. Just before it expired the anode was glowing bright yellow!!

Christopher Capener
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Interests in the collection and restoration of Tefifon players and 405 line television
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