> From: Randall Young [mailto:randallyoung@earthlink.net]
> Sent: Tuesday, October 05, 1999 1:39 PM
>
> Your 6 cylinder, 4 cycle engine fires 3 times per revolution
> (each cylinder fires every other revolution), so the RPM
> should be 20 times the frequency in Hz. (eg 1200 rpm =
> 60 Hz) .
That's what I had figured out. But...
> However, depending on your DMM, you may get multiple
> counts per spark (the waveform on the coil is messy),
> which should be pretty obvious (reading 2 or 3 times what
> you expect).
My readings were pretty much equal to the tach reading (except that the DMM
was showing "sparks" per *second* and the tach revs per minute). ie. At
idle, the tach shows ~800 and the DMM shows approximately 800 Hz. That's why
I was puzzled by the DMM readings.
Is it possible I just have the right set of circumstances whereby my tach
and DMM "agree".
Note: I think my tach is reasonably accurate.
--- Peter Zaborski CF58310UO ---
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