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Old 29th Jan 2010, 10:09 pm   #16
Phil G4SPZ
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Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Default Re: Magic eye valve types

Quote:
Originally Posted by Leon Crampin View Post
I had a TV-7/U tester once... I think with a little creative thought, most testers can be configured to test an eye but I'm not familiar with the TV-4A/U.
The TV-4A/U is a simple 'tube checker' rather than a valve tester, and measures total emission only, by applying around 30 volts AC to the electrodes and measuring total cathode current via a meter with a calibrated shunt.

Thanks to everyone for their suggestions. The www.magiceyetubes.com website suggested by Mick is a real mine of information and gives me practically everything I need to know. Interesting facts are that the design life of a magic eye is around 1,000 hours, and short of boosting the target potential it seems there is little that can be done to rejuvenate expired eyes.

Great stuff, thanks again,
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