On Thu, 23 Jun 2011 19:31 -0400, "John Ferrell" wrote:

> > Here's a clock that uses the stepper motor from an Apple ][ disk drive
> > for power, the motor body is spun by belt drive from the spindle
> > motor(not shown):

> I would not have considered a stepper motor.
>=20
> The cheap brush type hobby motors work fine. When I was working for IBM=20
> I had
>   a few occasions to mechanically attach one of these motors to a=20
> spinning shaft
> and scope the output. The voltage was a good representation of the=20
> velocity but

The stepper (it was an old 12 volt one) gave me enough voltage at a low
speed, so that was the only reason I used it. Propeller clocks are noisy
and hard to balance, so the slower the better :)

Cheerful regards,

Bob

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