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From: martin@mwtech.UUCP (Martin Weitzel)
Newsgroups: comp.unix.sysv386
Subject: Re: SCO Unix, ALR FlexCACHE losing time
Message-ID: <1028@mwtech.UUCP>
Date: 3 Jan 91 20:30:20 GMT
References: <1991Jan01.162400.6155@litwin.com> <1991Jan2.221527.15181@gsm001.uucp>
Reply-To: martin@mwtech.UUCP (Martin Weitzel)
Organization: MIKROS Systemware, Darmstadt/W-Germany
Lines: 29

In article <1991Jan2.221527.15181@gsm001.uucp> gsm@gsm001.uucp (Geoffrey S. Mendelson) writes:
[...]
>1:  The battery backed up clock loses (or gains time).  
[...]
>    A friend of mine had an early Tandy 3000 (mitsubishi m/b) that lost 11
>    seconds a day.  TANDY fixed it by replacing the motherboard.  It lost
>    12 seconds a day.  On the third try they said it was within specs.

>    I know of no published specs for clock accuracy. 
[...]
>Also a note on accuracy:

>    1%  would be 864 seconds a day or 14 minutes 24 seconds
>   .1%  would be 86  seconds a day or  1 minute  26 seconds
>   .01% would be 8.6 seconds a day
>   1 second a day is 1/86400 or 1 in almost 1 part in one hundred thousand.

From some ancient times when I spent my days with a soldering iron and
electronic components on my desk, I remember that the commercially
available x-tals (which were also affordable for my budget) had an
accuracy of ~10e-6..10e-5 which means that at most one second within
a day would be in the specs.

As a related topic: I've heard that there are some commercially available
receiver boards for PCs that decode radio station which send time signals
on long wave (in Germany "Sender Mainflingen" of the PTB). Does anybody
have experience with such boards? Drivers for UNIX?
-- 
Martin Weitzel, email: martin@mwtech.UUCP, voice: 49-(0)6151-6 56 83