[time-nuts] 1903 Self-setting / self-winding clock
paulswedb at gmail.com
Sat Nov 1 11:34:04 EDT 2014
I can't speak to the pendulum swing. I had seen clocks that did indeed have
some form of mechanical lockout like you mention.
So yes you are on target. Now we get to a bit of nitty gritty. When does
the pulse arrive I suspect at 59:59. The goal is that the clock rolls up to
0 and is released by the pulse perhaps.
So I mentioned that the pulse would be a higher voltage and 10-20 ma pulse.
Thats telegraph behavior and if the telegraph coils not in the clock then
as you say you are dealing with a 3V at some current pulse.
One suggestion was a relay. Absolutely will work also solidstate relays
they are cheap today and easily driven from a micro or traditional logic.
I also suggested and agreed just buy a $21 maybe gps module as the source.
They are really good cheap and very accurate.
OK how about those pictures you mentioned? :-)
Now as the saying goes "Just do it".
On Sat, Nov 1, 2014 at 11:06 AM, Mike Baker <mpb45 at clanbaker.org> wrote:
> This particular 1903 Railroad self-setting/winding
> pendulum regulated clock needed only an hourly
> signal from a Western Union telegraph line to
> provide momentary closure of a relay contact.
> This supplied +3 VDC to rewind the spring and also
> reset the sweep seconds hand on the hour, every hour.
> From what I have learned about this, the resetting of
> the sweep seconds hand is mechanically coordinated
> to occur when the pendulum is at either end of its
> swing. It appears that is no way (that I know of) to
> guarantee that the "telegraphed" reset pulse would
> coincide with either end of the pendulum's travel.
> Apparently, the resetting of the sweep seconds hand
> will only occur within the time frame of any single
> pendulum swing. I suppose this means that the clock
> might be in error by as much as nearly one swing of
> the pendulum because it has to reach the end of its
> swing before the second hand is reset.
> Just guessing here, but I am thinking that all this
> clock needs is a 1-second long closure of a relay
> contact on the hour, every hour. I don't think
> that leap-seconds are an issue here as the clock
> can be manually adjusted for that whenever a leap
> second occurs. So-- it comes back to counting
> 3600 one-second pulses from a GPS clock...? Or
> am I missing something here...?
> Mike Baker
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/
> and follow the instructions there.
More information about the time-nuts