Splice into your "tach" signal.
B. This is a 33k ohm resistance resistor, from Radio Shack.
C. This is where the wire splits into two. One wire splices on
and goes through
D. The potentiometer, where it goes in a side terminal, and out
the center one.
E. The positive wire then connects to the 1/8 inch mono plug
center terminal. The negative (grey) wire connects to the outer
terminal. Wrap each wire in electrical tape, so that the positive
and negative ones don't touch. Then screw the end cap back on the
back side of the plug.
Note: C is where the wire splits into two: one becomes the
positive side, which goes through the potentiometer. The other
continues straight to the mono plug, acting as the ground wire.
