Another approach uses no sticker, no alarm, no "anti start switch", =
nothing obvious.
I had a truck that had a neutral safety switch and a clutch switch (the =
result of changing from a 3 speed to a 4 speed. If it was started with =
both clutch down and in neutral everything was normal. But if started in =
neutral without pressing the clutch, or started in gear with the clutch =
pressed, a circuit was activated which gradually began to reduce power =
to the coil. Results it started ok, but before you could get out of the =
parking lot it would be misfiring and backfiring to the point it became =
undriveable. This made it appear not worth stealing. It was a fairly =
simple circuit, the key was a high power "P"channel mosfet source to B+ =
Drain to Coil+ Gate to a cap that was slowly charged through a resistor, =
when the Gate was no longer below the Source the Drain was fully open, =
but the cool part was while the mosfet was acting as a voltage =
controlled resistor and had it misfiring.
$.02 Lonnie - KF4HAZ -

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