"Gary L. Woodruff" <woodruffrep...@frontiernet.net> wrote in message
news:VHCIm.10450$fE2.9546@newsfe04.iad...
> howdy, I have this monster RCA that is possessed. It will turn on and
> then at random intervals will shut down and power back up. I have
> touched up any solder connections that looked cold. I removed all of the
> tact switches from the front panel control, problem still exists. I
> disconnected the front panel after the set was powered on and still get
> shutdown/startup. the set does not stay on long enough to develop raster
> but does have the HV static on the screen. I am thinking it is the power
> IC but do not have a print. Any and
> all help is greatly appreciated.
> thanks, Gary
There's something of a tradition in the repair trade of routinely replacing
all the (physically) smaller electrolytics in the PSU when there is random
triggering of protection circuits.
If you don't have an ESR meter, start by visually inspecting the larger
elecrolytics to see if the top has bulged or the shrink on label has started
to shrivel.
Sometimes a failing electrolytic will run noticeably hot, but be aware that
the aluminium can may not be isolated when you stick your finger on it to
sense temperature.
Alternatively, place a flake of candle wax on top of the capacitor, if it
melts the cap likely has a high ESR and the internal losses are producing
heat - if it gets hot enough to melt hot melt glue, put your safety glasses
on it may be about to explode.
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