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Old 02-14-2022, 03:20 AM
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Airedale Airedale is offline
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Join Date: Jul 2020
Location: Western Washington
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Quote:
Originally Posted by zeno View Post
Good call E M

This set uses a FBT winding so at 15Kc's. They did make brightener /
isolation in the day,, just use the right kind.
2 tricks for basket cases.
1) there is almost always a one or two ohm resistor in series with the F.
Just jump it out, it will bring the F up to abt 8 V
2) On older sets with an open FBT core you can add one turn to
the F in series. This should be done with a scope so you dont
go too far.

73 Zeno
LFOD !
Jumping a resistor seems like a fairly easy way to increase the filament voltage.

So is their a difference between a FBT and an "open FBT core"? What does it mean to add a turn to the filament in series?

I have also come across an article on how to build your own basic CRT rejuvenator. If this increase in filament voltage does not bring about satisfactory results then perhaps an attempt would be worth it.

https://jestineyong.com/restoration-...uvenating-crt/
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Last edited by Airedale; 02-14-2022 at 03:28 AM.
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