[sdiy] MIDI help

[Ingo Debus]

male man wrote:

 > i havent been able to trigger the ensoniq or fatman
 > with any of the other stuff so im not too sure they
 > work 100%(got them used), but i cant get anything to
 > trigger so i think im doing something wrong.  im using
 > 2 different brand new midi cables.  i tried messing
 > around with different midi channels, but no luck.  is
 > there something im missing?  is there a combination
 > that will be most likely to work most easily?  thanks
 > for the help, im going crazy here.

If you have made sure that it's the receiving device (checked with
known good equipment on the transmitting side), it could be the
optocoupler at the MIDI input is fried. If you can, check its output
with a scope while the unit is receiving MIDI data. There should be
some TTL level signal, if there's only a constant 0 or 5 volts, it's
time to replace the optocoupler. The optocoupler is most likely a 6
pin or 8 pin DIL (or perhaps SMD with newer gear) near the MIDI in
jack. Shouldn't be hard to find.

Ingo