PCB Bugs / Errors

Despite our best efforts there are a few small bugs in the PCB layout. This page will serve to document all PCB errors and the fixes required. Additional help troubleshooting build problems can be found at the Vintage Korg group: https://vintagekorg.groups.io/g/Maillist

Errors

1. C22 is not connected to ground on the top of the PCB as it should be. You can fix this by soldering a jumper between the grounded leg of C23 back to the ungrounded leg of C22. The ground leg for C23 can be see on the top face of the board, it is the leg closest to the board's edge. Connecting this leg to the adjacent leg of C22 (also closest to the board's edge) will fix the problem. [Discovered February 2016.]
2. R52 is not connected to ground on the bottom of the PCB as it is on the original. If you compare the new PCB to an original one you will note that the trace is missing. You should be able to jumper or solder-bridge that leg of R52 to it's neighbor R51 which is connected to the ground. The MG circuit will not work correctly without this fix. See: https://vintagekorg.groups.io/g/Maillist/topic/36385877#2370 [Discovered 4/17/2010]
3. Some constructors of the KLM-367A may have noticed that the MG delay control is not working correctly. This is caused by a missing trace between one end of R98 and a nearby through-board-hole. Oddly, the prototypes functioned fine despite this problem. The error is easily corrected with a small jumper on the bottom of the board from the leg of R98 to the through hole. See the photo below for details. [Discovered 4/27/2010]

Other Things to Note

1. Some boards have displayed an instability which is characterized by random resets or other strange behaviors (multiple lights on at once, etc.). The cause of this is thought to be very slightly different routing of the traces on the circuit board near C23. If your board exhibits strange behaviors this can be corrected by replacing C23 with a 10pF ceramic capacitor. This alternative capacitor is now listed in the parts list. (See https://vintagekorg.groups.io/g/Maillist/topic/36385911#2556)