--- In
Simmons_Drums@yahoogroups.com, Tony Henderson <tonyhenderson@...> wrote:
>
> Hi everyone....I've recently come into ownership of an SDS7 kit. It's a basic 5 - drum pad model ( kick, snare, three toms ) and it also has a kit selector pad. I've now discovered that there's a problem with the " brain" in that the whole right - hand, programming and selector part of the module has an intermittent power fault and the LED display with the rotary selecter switch doesn't light up at all. I'm no electronics guru so I've no idea where to start. Is there anyone who does an accredited repair service for a Simmons of this vintage in the UK ? Am I even wasting my time trying to GET it repaired ?? Any pointers gratefully recieved....
Very carefully clean the edge connectors and check that the keys that line up with the keyway in the edge of the board is correctly fitted.
Remove the battery, and check ∗very very carefully∗ that it hasn't piddled electrolyte all over the board. This is extremely difficult to fix. Search for similar battery problems with Korg Polysixes if you want to know the full horror.
Check the power supply outputs carefully. IIRC they are +/-15V DC and +5V DC. As long as the 15V rails are reasonably close and +5V is within about +/- 0.2V it should be good. Check the PSU ripple under load.
DO NOT "RE-CAP" IT. You'll only give yourself even more faults. "Re-capping" equipment pretty much only ever makes things worse. Electrolytic capacitors just don't fail in equipment like this - about the only place you'll find genuinely faulty electrolytics is in very old (1930s-ish) equipment, and modern cheap crappy switched-mode power supplies. In something like 20-odd years of repairing electronic equipment I've found about a dozen electrolytics that were genuinely faulty, and only one of those in a synth - my own Polysix ;-)
Now, disc ceramic capacitors, they're another story altogether...
--
Gordonjcp MM0YEQ