[time-nuts] Antique pendulum clocks

[Adrian Godwin]

On Thu, Nov 21, 2019 at 2:01 AM Bill Beam <wbeam at gci.net> wrote:

> Most people interested in this problem have been dead for about 200 years.
>
> I knew there was a reason why I didn't feel so well lately ..


I have an electric pendulum clock by Bulle. A coil swings in a short arc,
following a curved magnetic polepiece. At some point, contacts close and
provide a timed sustaining impulse to the coil.

Out of sheer pigheadedness, I am attempting to monitor the movement with
antique (perhaps not quite so antique) timing equipment. I have an HP456A
current probe to capture the impulse instance, an HP 5275A counter to
measure the period and an HP101A oscillator to provide a reference. ADEV
calculations might be done by an HP9815 calculator or perhaps an HP41 if I
can't find the 9815's parallel interface. Non-HP equipment is permitted but
nothing suitable has come up so far.

A difficulty at the  moment is that the contacts bounce somewhat, making
the impulse timing poorly defined. I haven't yet got as far as seeing any
mechanically caused pattern to the errors.

Thanks to Tom for giving me more distractions to read :)