Ibm p202 problems

Hi I have an IBM p202 that has problems at some scan rates it has a pin cousion problem, (sides bowed in) pin cusion correction has no effect when the fault is present. also at most scan rates it has a horizontal flickering lines. Both problems clear up if the moniter warms up. Someimes it will jump between normal and bad pincusion rapidly as it warms up. Here is what I have tried so far. I took it apart and found a section of the D board that was heat sensitive. Heat it with hair dryer it clears up almost instantly, blow cool air on it with hair dryer it starts messing up almost as fast. I suspected bad elerolitic caps replaced all of them in this area, still has same problems. This board has SMT components on the bottom of board I didnt mess with them. I didn't notice any bad solider joints. Poking and prodding the board didn't seem to have an effect on the problems. Any suggestions besides toss it to the curb or take it to a tech?

Reply to
Chance
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Switch the monitor off. Pick out a component on the faulty board and heat it with the tip of a soldering iron. Switch monitor back on and see if fault clears. Repeat until you find the bad component. You can use a can of freeze spray alternately with the heat to confirm the bad part.

I'd certainly want to reflow all the solder joints with fresh solder though. Electrolytic caps would be my first suspect, but as you've eliminated them bad solder joints are a strong possibility.

Dave

Reply to
Dave D

Some components, especially capacitors have become thermo sensitive. The fault is most likely in the pin amp and horiz scan areas.

We normally use a heat gun and freeze spray to troubleshoot for this type of fault.

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JANA
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Reply to
JANA

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