wells gardner 25k2193 monitor problem picture compressed

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wells gardner 25k2193 monitor problem picture compressed

the picture is compressed into about an 1/8" line running right to left. i assume that is a vertical line since the monitor is on its side. no obvious problems on board i checked solder joints on flyback they are okay. the horizon yoke connection one lead has been hot (the red wire has turned the plastic connector dark brown on just that lead). any ideas where to look or test.
thanks
 
Has the monitor been recapped and checked for cold solder joints? Does it have all the U2000 upgrade kits installed?
 
After capping it:

Check the vertical IC for shorts. If you find any, replace it. Also, there is a diode and resistor (D302 and R303) that can go bad and cause the vertical to go out...
 
i can tell that someone has replaced the flyback and also some caps in the past. i checked the d302 and it does give me the same reading both ways so it must be shorted. if that is shorted should i be looking anywhere else or replacing any other components or just the diode??
thanks
 
If it's shorted (reading under .100 both ways) then you should also check R303 for an open also, as it will most likely cause D302 to fry again. And check the vert ic (U601) for shorts too...
 
i can tell that someone has replaced the flyback and also some caps in the past. i checked the d302 and it does give me the same reading both ways so it must be shorted. if that is shorted should i be looking anywhere else or replacing any other components or just the diode??
thanks

Thats right don't forget the Ic TDA1771 cause pin9 has
around 95 ohms on it, its shorted you can also tell if you look at it good.
you might see a hole in it.
Anytime that happens the supply voltage parts will fail, like R303 and D302.C305
and C613 the 100uf pump up cap needs to be replace as well,if never replaced.

The symptom you can get from this failure is,No picture HV and neck glow
sometimes you have a horizontal line,loss of vertical deflection
may have had a smoke smell complaint for someone,Check R303 first!!
The Ohm's on pin 9 of Ic should be high if good. Or it will burn up D302 and R303
R303 needs to be the correct ohms or it will effect the vertical size.
Also common to U5000 same parts and same locations
With the SB you can skip the Mosfet fix thats only if the It is bad only at the time.
the others you should do. also replace Q708 the 2sc2482 for intermitent failure
if resistors test good then just Q708 and Q703 and vertical kit.
 
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