>well, on my friends bugeye'd sprite, the tachometer was electrical, and
>measured the RPM by means of an inductive pickup off the wire bringing
>12 volts (originally ground) to the coil. when the points closed, and
>the coil charged, a current would flow in the wire which would induce a
>voltage inside the tach.
>i guess the tach's really didn't work that well, since they soon changed
>to a gear-drive tach, with the pickup off the generator (not alternator),
>of all places!
Uh, I think you're confused. The Bugeye's (and the Mk II's) had mechanical
tachs run off the generator (via a hard-to-find little gearbox). Starting
with the Mk III (1098cc, roll-up windows, etc) they switched to the
inductive tachs, which were used for the rest of the sprites and midgets.
Also interesting was that the inductive tachs would vary their readings
slightly depending on whether the lights were on (voltage drop).
The inductive tachs do seem to have survived better than the mechanical
ones, in general.
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com BIX: rjesup
Common phrase heard at Amiga Devcon '89: "It's in there!"
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