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Roland PG-200 problem

Roland PG-200 problem

2012-06-08 by Mark Wallis

Hi folks, i have a JX3P in with PG200 programmer. One of the 100uF caps had blown, all electrolytics have been replaced and voltages are correct throughout the board. None of the pots are doing anything, most of the switches are working. Am I looking at a CPU failure? the JX3P seems to work perfectly...

Best Whooshes, MSW

Re: Roland PG-200 problem

2013-01-17 by Boddington

Hi there -

I know this post is old but it's always sad to see an unanswered question.

You'll see several 4051 multiplexer ICs in a row. Those interface between the pots, the cpu, and the JX. Check the voltages (or do a diode check) on these. You may find that several of the pins are blown. It wouldn't be uncommon for these ICs to have reached their end at this age. Also take a look at and test the TL082 opamp and the LM311 comparator. You may find damge there too.

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