[time-nuts] Watches

[Didier Juges]

I believe watchmakers have a device they use to measure the vibration from
the stepper motor or the escape mechanism and indicate if the watch gains or
looses time. I am not sure how accurate that system is, and if something
equivalent is in use on crystal watches.

Chuck, can you tell us?

My son's Bulova was at the repair shop for something like 3 months
(August-November, I got it back last week) for what I initially thought was
a dead battery (the watch was erratic). The watchmaker said a capacitor had
to be replaced (did not ask which, I assumed it was the trimmer capacitor).
He further said the factory sent the wrong capacitor 3 times, after which he
decided to replace the entire movement instead, hence the 3 months and $60
repair (after discount).

I am not sure if my son's watch is crystal controlled or some other system,
I know some Bulovas used to use a mechanical tuning fork resonator
(Accutron?) His watch is only 2 or 3 years old.

Didier

> -----Original Message-----
> From: time-nuts-bounces at febo.com 
> [mailto:time-nuts-bounces at febo.com] On Behalf Of Chuck Harris
> Sent: Saturday, December 01, 2007 8:45 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Chronometer contest sponsored by 
> IEEE Spectrum
> 
> Hi Max,
> 
> I haven't seen a quartz watch with a trimmer capacitor in 
> something like 20 years.
> 
> What they do now days is use a microprocessor with flash ram, 
> and the timing machine reprograms the microprocessor's second 
> counter to trip at the right time.
> 
> -Chuck Harris (amateur watchmaker)