- Turn all MIXER switches OFF.
- Insert an S-Trigger plug.
- Set CUTOFF FREQUENCY control to -1.
- Rotate FILTER EMPHASIS control fully clockwise.
- If regeneration does not start when the FILTER EMPHASIS control is between 7 and 8, set the control to 7.5.
- Adjust the 'Regen Cal' trimpot (located on the Filter Board) clockwise until regeneration just starts.
- Verify that removing the S-Trigger plug stops the sound.
Source: MINIMOOG — minimoogservicemanual (manual)