K7400 Vertical Collaspe ? Fold over ? You make the call.

Neck board good
TP205 25 volts
Vert IC replaced problem still exist
Remote board/wires good and verified
 
you say the remote board wiring is good but are the V. Hold and V. Size pots good? adjusting to vertical collapse would suggest V. Hold is wonky
 
Yes. The wire harness and remote board was used with another chassis. So maybe something in the V HOLD circuit? The image is stable.
 
remote adjustment boards for that are typically stable. clearly vertical deflection issues but why? could be a corrupt tda1771 or related components. caps, low b+ power to it, something else.
if you want it repaired reconditioned analyzed and taken care of / done feel free to use my services.
 
Have you check the associated components for vertical as mentioned in the WG repair guide? (copy attached)
 

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yes. It was mentioned this needs the vertical pin cushion board bc it's the 23' version. Ill try later
 
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I think I have a U5000 like this. I would guess it's probably a resistor out of spec in the 600 section. I don't know if bad TDA1771 would look like this. I watching a zeno video, to test the vertical IC you just test the diode on the other side of the heatsink. if it's anything but junction drop or dead shorted (not your case) then the vertical IC is bad.
 
Going to remove the TDA1771 and replace with a known good one today. All resistors in 600 section test fine. This one is not pressing so it's going on to the back burner for now. I will test voltages on IC too when I get a chance.
 
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