Interesting comment about non-self-starting clocks. I have an old “FDR” clock with a synchronous motor; it has to be started by spinning a knob on the back. The case has molded into it the words, “F.D.R., The Man of the Hour.” I suppose it dates from just after 1933 when Roosevelt became President.
A couple of my HP quartz frequency standards use non-self-starting dividers to take 1 MHz down to 100 KHz. Failure of either power or signal causes the divider to stop; a manual restart button is used to start the divider. Loss of the 100 KHz output is thus a signal there has been an interruption. J On Sat, Feb 13, 2021 at 12:55 PM Thomas D. Erb <[email protected]> wrote: > My firm has electrictime.com - sold power station master clock as part > of Telechron - now we just make big tower and street clocks. > > We have a bunch of master clocks in our museum - two in our on-line > exhibit - I'm hoping to get a small article in IEEE Spectrum. One master > clock was made in an vacuum chamber with an invar pendulum. > > My clocks are shown > https://electricclock.omeka.net/items/show/6 > https://electricclock.omeka.net/items/show/12 > > Mark Frank has some restored units at > > http://www.my-time-machines.net/master_clocks.ht > > In the 1970's we made a cheap power station clock for some islands - it > consisted of a synchronous wall clock next to a quartz battery power clock > - the operator keep the synchronous clock in phase with the quart clock. > > BTW the little red flag was a part of a patent fight - Telechron had a > patent on self-starting synchronous motor the non-self-starting clock > companies got a law or regulation that a clock had to had a notification > power had been off - they thought they had him - but he came up with a > creative solution. > > > > Thomas D. Erb > p: 508-359-4396 > f: 508-359-4482 > a: 97 West Street, Medfield, MA 02052 USA > e: [email protected] > w: www.electrictime.com > Tower & Street Clocks Since 1928 > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > -- Jeremy Nichols Sent from my iPad 6. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
