[time-nuts] Measuring the accurcy of a wrist watch

David C. Partridge david.partridge at perdrix.co.uk
Sat Apr 19 04:33:47 EDT 2014

I too tried that and equally failed even with 52dB gain.  I suspect that
part of the trick is how the piezo is mounted: Quite possibly if mounted in
a circular form held only at the edges, with the watch crown touching the
centre it might be more sensitive than if the centre is clamped to the watch
with the edges free?

David Partridge 
-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Robert Darlington
Sent: 18 April 2014 19:49
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Measuring the accurcy of a wrist watch

Commercially they use piezo transducers ("bender disks") in direct contact
with the watch to hear them tick.  I did my best to build one up several
weeks ago.  I could hear ants walking but my cheap swiss movement was just
too quiet.  It was amazingly quiet, even going through a preamp and dialing
the vertical amp to 11 on the scope.  They must have them sized for
resonance a little closer to the spectrum given off by the movement.


More information about the time-nuts mailing list