Vintage Simmons Drums (UK) Users Group

I have an SDS6 that has an issue with the scan on the matrix.  Everything works.  The Led’s lite with the pattern but when you play one the unit doesn’t scan.  I assume it is an internal clock because if I inject an external clock it works.  I assume there is a chip that needs replacing.  Wondered if anyone could point me in the right direction.  Maybe the 311 chip after the tempo pot circuit?


Jim Barber
lewisbarber@...