[time-nuts] FWD: 60 hz as a time standard [telecom]
Hal Murray
hmurray at megapathdsl.net
Mon Oct 31 07:02:50 UTC 2011
A fun story from comp.dcom.telecom on usenet
------- Forwarded Message
From: "Martin Bose" <martyb at sonic.net>
Newsgroups: comp.dcom.telecom
Subject: 60 hz as a time standard [telecom]
Date: Sun, 30 Oct 2011 8:42:11 -0700
Organization: The Telecom Digest
> At some point in the 1930s or shortly later, the commercial power
> grid became reliable enough to use the 60 Hz as a means to run
> clocks accurately. This led to the loss of pendulum regulator
> clocks and Western Union time signals
Many decades ago my Uncle was a district manager for PG&E, and one of the
perks was a cabin at a turn-of-the-century hydrogenerating facility that
had been automated a long time ago. His cabin was the plant manager's cabin
originally, and in the living room was this neat clock. It was a tall
grandfather clock affair, with a temperature-compensated pendulum to keep
it accurate. It had one large dial with a smaller one inset in it. The
smaller one was a conventional clock face; the big dial had a single hand
that read zero straight up and plus and minus seconds on either side. The
mechanism had two clock drives, the pendulum one and an electric one driven
by the power station generator output, and the big hand kept track of how
far the frequency from the generator had drifted. I never saw it read
anything other than zero, but it wasn't hard to imagine that in the
manually controlled days a glance at that clock might have resulted in a
phone call to the plant operator to get the fequency back on track.
Marty
------- End of Forwarded Message
--
These are my opinions, not necessarily my employer's. I hate spam.
More information about the Time-nuts_lists.febo.com
mailing list