Vintage Synth Repair

> I'm having trouble finding a datasheet for a 68B09 processor.  Does 
> anyone know where one is posted?

Just look for 6809 or MC6809 or M6809.  It's a standard Motorola
8-bit microprocessor from the 1979 onward.  The B is just a slightly faster
crystal.  If there is an E on the end, then it has a different clock drive
circuit.  There's going to be RAM chip too in order for the stack to
work, so if the RAM is toast, the program is too.
 
> The G- (pin 20) of the 2732 seems to follow the system clock (1MHz) 
> which is screwy.  Anyone have a ecopy of the logic portion of this 
> part of the schematic?  I'm starting to think the processor may be 
> bad.  I don't want to invest in a full set of schematics since this 
> whole unit may be junk.  I'd like to at least see if the processor is 
> trying to read data from the eprom.

Yeah, sounds like it's just cycling the data and/or address lines.  The
2732 would be mapped to the top of the 64k so there should be
some decoding like a 74138 or discrete logic.  It may include the
R/W* line.  Also check the RESET signal.  Does the wave at G*
change when the ROM is removed?

GB