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Maarten · 1st Jan 2014, 4:41 am

As long as the problem is in the cathode rather than in the emissive layer, any valve can be rejuvenated with varying degrees of success. It never hurts to try!

Simplest test could be to let it glow at an elevated heater tension (for example 8V instead of 6,3V) for a few minutes. Then plug it back into the set and see whether there is any difference at all. If there is, some improvement should be possible. Also if the valve is operated at a higher heater tension while in the set (or in a test setup) and the eye is much brighter at 8V this shows the emissive layer still has some life left.

1st Jan 2014, 4:41 am	#5
Maarten Dekatron Join Date: Dec 2007 Location: Haarlem, Netherlands Posts: 4,199	Re: Rejuvenating Magic eye Valves? As long as the problem is in the cathode rather than in the emissive layer, any valve can be rejuvenated with varying degrees of success. It never hurts to try! Simplest test could be to let it glow at an elevated heater tension (for example 8V instead of 6,3V) for a few minutes. Then plug it back into the set and see whether there is any difference at all. If there is, some improvement should be possible. Also if the valve is operated at a higher heater tension while in the set (or in a test setup) and the eye is much brighter at 8V this shows the emissive layer still has some life left.