Yes you are correct that the correct path to go is to properly test and identify the fault, seek out the cause then rectify that cause. This is all good in a perfect world where the person attempting the repair has ALL the required test equipment required to carry out proper fault diagnosis. In this case I am assuming the original poster may not have access to such test equipment thus is seeking direction from those who may have had experience in such repairs. The suggestion to simply replace the mux components won't identify the fault nor it's cause yet if it worked then we have one happy SDS user.
My experience with the SDS9 showing such symptoms was faulty 4051's in the mux. I myself don't see that one faulty TL084 will cause the unit to behave the way it is.
I have had one unit display the random triggering problem that required the use of a logic analyzer hooked to the address ,data buss and chip select lines to diagnose what was going on. To be fair I don't think too many people have that sort of kit. Yes it's all in a days work for ppl like myself but I have spent years in the business and accumulated some very expensive test gear over time. Lets give the guy a break and do what we can to help him (or her) out as best we can.
--- In Simmons_Drums@yahoogroups.com, "gordonjcp" <gordon@...> wrote:
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> --- In Simmons_Drums@yahoogroups.com, "simmonssds7fan" <ptmetcalf@> wrote:
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> > Progress report: replaced IC61 and the six 4051 demux chips, no real change other than the sound generation is a bit stronger. The original random triggering issue is still there. The TL084 chips arrive tomorrow. I'll see what transpires after the replacement of those. Starting to lean towards IC58 being the problem, but I guess it won't hurt to replace those TL084s either.....
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> Yes, it can hurt to replace those TL084s. Are you just randomly replacing bits one at a time and hoping you get lucky?
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> ∗TEST∗ - then, if the part is faulty replace it. Don't just charge in and start ripping parts out hoping that this one, maybe, might just be the faulty one.
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> --
> Gordonjcp MM0YEQ
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