speedometer replacement

[Ralph L. Fullenwider]

There was a thread on this some time back about a speedo replacement from
Stephen B. I ordered one as well and had no problem in figuring the math
and programming the new speedo. What I did have a problem with was an extra
wire coming from the back of the unit, one was grey and the other blue. The
grey powers the hot side of the magnetic sensor, I took the blue to be a
ground and was wrong about the blue, removed it out of the circuit and the
speedo worked very well.

I found some calculations on line for the programming. my tires rotate 502
times per mile and that times 60 teeth on the BB drive drum times the
constant give you the ones and 10's binary switch positions and using the
sum of that equation plugged into a second constant give you the hz rate
figure to set the switches up with. Speedo is good and replaces the
original exactly. Thanks Steve

Safe travels,

Ralph and Charolette Fullenwider
"84FC35 "Ruff Diamond"
Duncan, Oklahoma