Message text written by Fred Fillinger
>For door ajar, you can pop-rivet springy tangs or coils, out of a
> > battery compartment from junk electronic stuff, to contact each shoot
> > bolt, wired in series from through the internal metal of bolt
> > mechanisms, port to starboard, to a ground. You'll need an NPN
> > transistor circuit to sense an open:
> >
> > Tie base and collector together to really annoy the transistor. 14V
> > through LED dropping resistor to base-collector. LED from emitter to
> > ground. Base-collector to the shoot bolt circuit open end. It's an
> > unswitch - when shoot bolt switch turned on, grounding base, it
> > doesn't do anything. The triple-duty resistor also limits current
> > flowing through exposed door hardware and minimizes effect of
> > dirt/grease on the shoot bolts.
> >
> > Further, seems you can take the ground from the shoot bolt circuit
> > through a lever-type microswitch in the throttle housing, affixed to
> > close at above runup throttle position. No door alert until plane
> > thinks you're taking off; could even quick-nudge the throttle in runup
> > to check the doors. But that could make you insufferable at a fly-in,
> > showing off features like that.<
Sounds horribly complicated. I used a pair of microswitches and one light
per door - works fine.
Nigel Charles
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