An alternative if preferred would be to use a sub-miniature MIL spec rotary switch to switch between? common, off/slow/fast just as in the ND6T wiring diagram.
Just completed this board with no problems.
A screened pre-made wiring loom would help ensuring the exposed sections are kept nice and short. Choose good quality connecting wire and pre-solder the pads before tacking on the leads for best results. This is by far the easiest AGC board design to fit in my opinion.
Best wishes Derek G4VWI.?
