two lines on a vertical collapse? 25K7197

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Wonder if anyone could help on this chassis. it's been driving me nuts!...the problem has been a vertical collapse, but now with a twist..

This is what I've done so far:
Recapped, new flyback, reflowed everywhere I could see might be a problem.

new: IC2 and IC3
checked IC4 and Q11 (HOT-Q11 was shorted, so replaced), a la Buffet youtube video.

read up on KLOV threads and found R91 and D13. they were both shorted so I've replaced. In fact I replaced R91 first before checking D13 and saw it go red hot before quickly cutting the power. re-checked R91 and it was miraculously OK, changed D13, things seemed ok next time I turned on the power.

You think that would have resolved the vertical collapse, but now I have two lines in the middle that can be widened with the V-Pos pot (see pics).

would anyone have an idea what the next steps should be?

Oh and another important thing. I think things are getting too hot as the heat sink for Q11 and the big ceramic Cap screwed to the chassis get very hot quickly, close to too hot to touch. I'm not sure but worry this started when I changed the HOT (Q11). Is this normal or did I screw something up there? i've rechecked my work but don't see anything missed.

Appreciate any help thrown my way.
 

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I had one where the HOT (Q11) and resistor (R301) were getting hot. Found D18 shorted. Don't leave it on to long or you will fry the HOT and Voltage Regulator if your D18 is shorted.

I think now you have a vertical height problem not a vertical collapse problem.

Ed
 
not sure if I did this right but testing for 12 volts DC of IC1, in circuit, I hooked the black lead of my multimeter to the metal of the chassis and probed pin 16 (incoming voltage as per schematic?). I got 2.6volts..
 
yup your +12 is not there.

look back threw the circuit and see what resisters are open or out of spec.
there are not that many that feed the IC.

if that IC is not powered you will not have vertical deflection.

Peace
Buffett
 
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