This guide tries to cover basic troubleshooting: Some simple steps that can be taken by anyone with a multimeter and some spare time. This document is continuously evolving, so you can expect modifications and updates.
These steps do not try to cover everything, just the steps that would solve the most common problems after a kit assembly.
When everything is assembled, and before plugging the module power in:
- Are all components in their right place?
- Sure? Double check.
- Are all electrolytic capacitors soldered according to their polarity?
- Are all transistors and diodes soldered according to their polarity?
- Is the power connector properly oriented? Power cable you will be using as well?
- Are there any solder spots touching any other one close by? If you have doubts check the schematic and/or CAD files.
- Check if there is continuity between V+,V- or GND with your multimeter. If so, look for a short-circuit
- Do not place the ICs yet. Leave them until after the soldering work.
When all these questions have positive answer plug it in, then…
- Does your synth switch off or behave funny?
- Double check the cable and power connection. It might be reversed.
- Do any transistor or regulator over-heat?
- It might be reversed or placed in the wrong place. Double check this.
- Test for short circuits or funky solderings.
- Check that +12v and -12v power reaches the IC sockets as it should. Check their datasheets and/or CAD files to check which legs are power ones
- If no volts are present, double check power soldering points and paths for the ones that did not work.
- Use the multimeter to check continuity between the socket’s contact and soldered leg on the other side of the board.
- Insert the ICs, making sure they are in their right place, properly oriented and no legs are bent.
- Do any of the ICs overheat? Double check their placing and polarity
See the flow chart below to help with these previous steps. You can also download it in pdf or dia formats.
