Jim; Congratulations, that is a really nice looking clock!
You may have a real gem there. While the movement doesn't look like anything special, the pendulum looks like a Riefler. Which is something quite special...sort of like having a Thunderbolt inside your bedside alarm clock... Tom Frank On Aug 25, 2008, at 3:40 AM, Jim Palfreyman wrote: > Hi Folks, > > Well I've had the best weekend since I've just acquired a pendulum > clock > that used to be a telecommunication time standard in the 50s. It is > a German > made Siemens pendulum master clock that is about 150cm high and has a > full-length seconds pendulum which is about a metre long. It is > powered by > 48V to automatically wind the weight up and will maintain time for > about 8 > hours without power. > > The pendulum has an adjustment to raise and lower the 7.5kg weight to > calibrate the clock. One full turn of this knob will advance or > retard the > clock by 40 seconds per day. It is graduated into 100 divisions > enabling you > to adjust it within 0.4 seconds per day. Half way up the pendulum is a > little tray where you can deposit small weights for your final > adjustment > (and most importantly without stopping the pendulum!) > > Even though it's a master clock it is also designed to be > synchronised to > another master clock and so there is an armature on the pendulum > that can be > steered by a magnetic coil. I have no documentation on this bit, > but when I > figure it out I naturally shall be driving it from a 1PPS > reference. (See > photo.) > > There are numerous contacts that are designed to open/shut at > various times > including every second, every thirty seconds and minute. The photo > shows the > mechanism behind the clock face. > > By connecting the seconds contact up to my 5370B I tuned it quite > quickly to > be accurate to about a second a day. Which is about 10 microseconds > per > pendulum swing! I'm impressed a tick tock clock can do that. > (Although it > pales into insignificance compared to what Harrison accomplished.) > > It is beautifully constructed and now one of my prized possessions! > > (I'll put some more photos in another post.) > > Regards, > > Jim<IMGP4585.jpg>_______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
