Common Failure Points on the SSIO:
The SSIO seems to be a very sturdy design. Some failures I have encountered:
Bad chip sockets on A6 (RAM) and A7-A10 (ROM). (24pin sockets) **
Some components seem prone to damage by rough handling-- lots of times
470uF electrolytics CP1, CP13, CP47, and CP54 tend to break off. They just
help keep the +5V levels relatively ripple-free, but replace them anyway if
in doubt. **
According to a StarTech Journal entry, some of the early "Kick" boards had a
flaw where CP34 was inserted with its polarity reversed. The fix was to
either turn it around or cut it off completely.
The .047uF cap in the audio output section tends to break off sometimes as
well. (It's usually C139.) **
LED #3 also seems to be missing a lot (broken off).
SW4 (the reset switch to the Z-80) isn't very sturdy either. Sometimes
it'll latch "closed" and cause a constant reset state in the game. Test it
with your multi-meter.
Very early MCR games used SIPP-style sockets for the J1 and J2 connectors
with solid core wire ribbon cables interconnecting the boards. If you see
these REPLACE THEM IMMEDIATELY. They do really, truely, suck. **
Also check for cold solder joints on JP1 and JP2. Connecting and
disconnecting the cables causes cracking in the old solder and reliability
Do you hate those 24 pin "ribbon" cables as much as I do? I have a good
trick to replace them-- use a 50 to 50 pin connector (like a SCSI cable)
and go from the top of one header to the bottom of the other. Remember
that there's one pin left over (the SCSI cable is 25 pins wide-- not 24),
be sure to put the spare pin on the same side on both end of the
Keep and eye on those DIP switches. None of SW3's settings should be "on"
during normal operation. Switch 10 on SW1 should always be "off" for normal
Clay Cowgill engineered a TEST ROM which tests exercises a lot of the
devices on the SSIO board. Click HERE for a copy
of the ROM image and instructions on how to use it