Use you PC  to measure your engine RPM.

http://www.tunelab-world.com/rpmsound.html  for Cassio Cassiopeia or the
Compac iPAQ
http://www.wwnet.net/~rscott/rpmsound.html  for Windoze

I tripped over this on rec.aviation.homebuilt.  Sounds useful.

Doug Gray
RV6 wings (almost done)

There was a thread earlier about the complexities of
measuring turbine RPM.

Perhaps this software could be modified to work with a
turbocharger (?).

I haven't tried it, so I don't even know if it really works
with piston engines.

Charlie England

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