Richard,
Thanks for that - I gather this is a bit of a pig to work on so it's going in to a chap tomorrow - hopefully your info will be of use in the diagnostic process.
Regards
Jonathan
--- In Simmons_Drums@yahoogroups.com, "Richard" <warlandr63@...> wrote:
>
> Open the unit up and look for IC65 (A CD4051). The small dot on the IC is next to pin 1 on the IC so count along the IC from there and then back up the otherside till you get to pin 12. Apply a 5v carefully and quickly on then off. If the Hitom triggers the soundside of the unit is ok. IC65 provides the trigger pulses to the various voices so if the unit works when you do as I suggested, you need to start by replacing IC65. If all other functions of the SDS9 are working, this should fix the problem.
>
> Let me know how you go
>
> --- In Simmons_Drums@yahoogroups.com, "Jonathan" <capnfishy@> wrote:
> >
> > Hi,
> > After much procrastinating I opened up the brain, looking for obvious signs as to why the Hi-Tom isn't working & can't see anything -no fried components etc. Spent an evening trying to follow the circuitry using a bright light, magnifying glass & schematic but nothing obvious.
> > So not sure what to do now. My electronics isn't up to diagnosing this kind of stuff. Is there anyone on the UK who does synth repairs or a related business?
> >
> > Also, just putting it back together and found that the schematic I'm following doesn't show (or I can't find - entirely probable) the connections to the power switch. I nearly took a photo but thought "it'll be on the schematic". Oops. There are 4 pins, 11, 12, 24 & 25 and the mains supply, blue & brown then orange & black going to the transformer. Can anyone tell me which way round they go. Many thanks.
> >
> > Any help would be greatly appreciated as I've just started on fills in my drumming lessons & it's unsatisfactory doing them with a dead tom.
> > Cheers
> > Jonathan
> >
>