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Mike WB2MEP Mike WB2MEP is offline
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Default Dumb TV question

On Jan 28, 5:56*pm, "Charles" wrote:
"oldfogie" wrote in message

.. .
What is the purpose of the small neon bulb by the flyback on older TVs? (I
haven't noticed it in any modern tvs.)

A voltage clipper? *Neon lamps have very high resistance and then drop to a
low resistance when the gas ionizes. *About 60 volts, I think.


Zenith liked to use them on their mid 60's - early 70's tube sets.
They seemed to use them for several purposes in the horiz. sweep
circuit.
I remember some 16" - 19" B&W portables where the neon bulb lit up
constantly
when the set was on. I have a 25CC50 chassis color set that uses two
in series in the HV regulator circuit. They light for a few seconds
after the
horiz. sweep starts then go out once the HV comes up.

Mike