Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!casbah.acns.nwu.edu!squishy
From: squishy@casbah.acns.nwu.edu (Shishin Yamada)
Newsgroups: sci.electronics
Subject: Re: Sidereal Time Clock
Summary: 60Hz Timebase Notes
Keywords: Sideral Time Clock, Clock
Message-ID: <2390@casbah.acns.nwu.edu>
Date: 3 Jan 91 12:15:46 GMT
References: <5711.277c4a63@nuhub.acs.northeastern.edu> <5972@mint17.UUCP>
Organization: Northwestern University
Lines: 30

In article <5972@mint17.UUCP> wilner@motcid.UUCP (Corey S. Wilner) writes:
>From what I understand, using the 60Hz line as a reference for timing is not
>a good practice if you want any accuracy.  I have heard that cycles can be
>longer or shorter than 1/60th of a second and some cycles can be lost completely.
>Anyone care to comment on this with more substance other than my glaring
>generalities?!
>

Corey: So far, there have been many previous messages about the 60Hz
timebase of the AC line "being fixed-in-phase" with the rest of the nation.
I come from Illinois, and our state has the highest percentage of nuclear
power use in the U.S. brought to us by Commonwealth Edison (so far so good
:) ). Anyways, I used to hear the worst things from my high school
electronics teacher about Florida's infamous 'brown-outs.' I do believe a
lot of timing electronics does make use of the AC line (Most VCR's do), and
I'm surprised because Japan (biggest manufacturer) has both 50/60Hz @
100V rms. Their modern clocks now do not have a 50/60Hz switch.

One case in point is that the battery back-up mentioned will NOT be viable
with the 60Hz method.

Lastly, I'd like to apologize to everyone for the unintended 'echos' of my
original message. I'm sorry that happened, I do not know why it did, I only
see it once on our site (although messed up), and I have revieved a lot of
concerned e-mail about it.

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Shishin "Squish" Yamada		* BitNet: squishy@casbah.acns.nwu.edu
EE Class of '91			* Northwestern University
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