Re: Tech: Gottlieb System 1 power supply question

I think I'll replace it anyway since it seems to have some "off" readings compared to other SCR's I have. If it won't solve my low voltage problem, I'll just have to keep looking for the cure. Thanks Mark. -S (CARGPB1)

Mark Clayton wrote:
Steve:

The SCR is not required for the 5V regulator to function. It's
a "crowbar" overvoltage protection device that shorts out the
5V power supply if the voltage goes too high. This (should)
blow the fuse and thus protect the digital circuitry from the
overvoltage. On a test bench, you can simply remove the SCR
and the 5 V supply should work fine. If the 5V supply is
working OK, the SCR should do nothing when it's put back
in circuit.

-Mark
.

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