Sequential circuits samplers

Did you buy this broken?

Is the OS 3.0 or 4.3b?

Make sure all the voltages are good. It's easy to test this because the jumper wires between the two circuit boards have all this labelled.

Then make sure that the ribbon cable that goes to front panel board is good. Pin 1 needs to line up with pin 1. It's quite easy to plug the cable in wrong, also they seem to break a lot so check continuity of the ribbon cable with your multimeter to make sure all the wires inside are connected between the connectors.

Check for cracks in the solder joints for the front panel switches and cracks in the pcb, check for continuity of the switches to make sure that they actually work when you press them.

I would check that the main CPU is all working and that you can see things happening on nearly all the pins especially the interrupts (refer to the service manual, I think it's uploaded to the group somewhere).

Then the memory chips, then the eprom. Make sure you read the service manual as you may spot something that you want to check first yourself.





On Thursday, 9 January 2014, 3:21, "wgpena@..." <wgpena@yahoo.com> wrote:
 
  
Yes, I tried it without the floppy drive plugged in and it does the same thing. I will take a picture, but It seems to load of the floppy ok. But no sound or response from the front panel controls.