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MS9-29 with a green grid?

Velyks

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I've got (a different) MS9-29 that is showing a slightly diagonal green grid in one direction with what look like faint retrace lines. I've recapped this board already and the output transistors seem fine. Is anyone able to tell me where I should investigate?
Please ignore the bad adjustment. No adjustments fix the issue.

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I found a burned out 100ohm resistor in R316 (neckboard) and replaced it (and R306 for red and R326 for blue as well), only to be greeted by the lovely smell of it immediately burning out. Before it burned out the green lines on the screen had turned to white lines with a white haze.

Edit: Haven't powered it on again. Traced it further back and found a dead 470ohm 1/2watt resistor at R519, that just goes to the flyback though.
 
Last edited:
Check the diodes in the green circuit. A shorted diode will burn out a resistor.
 
check everything between the guns and the chip/transistors that drive it.
you could have a bad transistor or shorted ceramic cap too.
 
I ended up just swapping the neckboard with a known working neckboard and it's back to life!

I did test Q311, Q312, Q313 and Q314 on one of those little multi-component testers and they all seemed fine.
 
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