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Cursitor Doom[_4_] Cursitor Doom[_4_] is offline
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Default Transformer shot! (was scope SMPS/ capacitor venting)

On Sat, 20 Feb 2016 09:36:18 -0500, JC wrote:

The transformer secondaries go (on the left side viewed from the top of
the transformer).

1.5kV 1.0kV Gap/no pin HV Common 60 60 12 12 6
6
0


Well on that basis there may be nothing wrong after all.

As others have pointed out this PSU will not run happy without a load
and I don't know what would be suitable. When I worked on these I always
just left the psu connected to the scope. Lets face it, the scopes been
turned on at some point with the psu connected so its not going to do
much more damage and at least you will know the loading is correct. The
EHT multipliers on these break down internally on these.


It's not possible to test this board with it connected to the scope. On
this model, it slots inside the two main signal boards which make access
under proper, full working conditions impossible. Just *another* obstacle
I've faced with this repair.
The EHT multiplier has been totally disconnected all through my tests
except where explicitly stated otherwise.


In one of your pictures there are a couple of diodes that look messed up
(V1809 and V1811) near the bridge. They are supposed to be BY208-1000
(1000v rectifiers), I can see "40" on one, maybe 1N4007?


I like your thinking! But no, the one nearest the bridge is a BY208-1000
alright, the other one to the side of it is a BY134. They both tested
fine out of circuit.