Hi Mark,
I was waiting for some parts to come in and I thought
I would try the old CMOS self powered trick.
The stock Mazda RX8 crank angle sensor is not a bad
generator so I hooked up this circuit. It consisted of
one 914 diode and a 220 mfd filter cap and a .1 mfd
coupling cap.

At 70 ms or 857 engine RPM with the RX8 trigger
it generates about 2 to 3 volts DC which is enough
to power a CMOS 4050 or 4049 hex buffer.

The 914 diode I used has about a 1.2 voltage drop so it
was not ideal. One can buy .875 volt diodes which
would work better. Also now a days I think people
are using FET transistors as diodes with an even
lower voltage drop. That might help.

The CAS was located about .125 away from the trigger
wheel. Probably closer spacing would result in
a higher power supply and input voltage.

At higher RPM you also get more power supply volts.

Another trick is use a pulse transformer on the CAS
to jack up the power supply voltage. Something like a
1:2 turns ratio would probably work fine.

The scope picture shows the CAS signal on top
and the output of the CMOS 4050 buffer on the
bottom.

Probably not worth it as 12 volts is always available
in an airplane and a CMOS 4050 or 4049 will run off
12 volts.

Paul Lamar