Subject: Rewinding pc coil for 9-1270 Zenith boards ?? anyone know
inductance? 9-1270-02 9-1270-3 mod# SR3587
From: "Dave Moore"

Now with the coil reworked, it still shuts down on
some really bright scenes, but it has a very much
obvious improvement in tolerance. In fact it might
run for 15 minutes or more.
one.

Oh, one thing I forgot to mention was,
I replaced the Flyback origionally. I ordered the
part from http://www.slelectronics.net/fl.zenith.htm#


Dave, the problem is your replacement generic flyback. Every one I tried did
this, sometimes shutting down as soon as the CRT lit. Basically, one of the
secondary sources off the flyback is too high, I don't remember which one. You
need to fudge this voltage with a dropping resistor, or fudge the shutdown
circuit. The board is actually marked and cut for a shutdown pot that was
never used. It's near the front of the board (away from the flyback). You'll
need a schematic to locate this, but it's an easy mod that will allow the
replacement flys to work properly. BTW, those coils run really hot even when
everything is normal.

John Del
Wolcott, CT

"Nothing is so opportune for tyrants as a people tired of its liberty."
Alan Keyes

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