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Jon Elson[_3_] Jon Elson[_3_] is offline
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Default *BANG!* Done it again!

Cursitor Doom wrote:

On Mon, 08 May 2017 00:08:14 -0700, mike wrote:

It's been suggested that you shouldn't try to reform caps by slowly
ramping up the AC input voltages on swtichers.
Disconnect the load side before you reform caps.
Ditto for the switcher that is the HV supply. It probably doesn't like
having it's input voltages all over the place.

Many circuits are designed to operate under specified conditions.
Ramping up the AC is not a specified condition.


You raise some very good and interesting points here which I shall bear
in mind in future.
So far as the sooty EHT components are concerned, it would seem that
these can arise from a blown component elsewhere within the case; the
smoke particles thereby emitted are attracted to the EHT cabling due to
electrostatics. So quite possibly it's a red herring and there may be
nothing amiss with the CRT supply circuitry at all. It may simply be
evidence of a previously-fixed failure elsewhere.

Older gear with CRTs can have anazing amounts of black dust that has been
attracted to the HV parts. It can come from local air pollution, just
normal household dust, etc. not necessarily something that burned up.
If you had a major component burn up, then the whole inside of the case
would be black.

So, those black HV wires are not a sure sign of something burning.

Jon