From: "jannsen" <0482183881-0001@t-online.de>
To: rsgb_lf_group@blacksheep.org
References: <20040210184134.KTHX20454.tomts35-srv.bellnexxia.net@smtp.bellnexxia.net> <402A6646.4030006@virgin.net>
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Date: Thu, 12 Feb 2004 23:18:54 +0100
Message-ID: <1ArPAc-19FrkH0@fwd00.sul.t-online.com>
Subject: Re: LF: Timing GPS
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Stewart Bryant schrieb:
> If GPS is not an option, then NTP (clock timing via the Internet)
> might be an alternative.
>
> There is some info on accuracy at
>
> http://www.ntp.org/ntpfaq/NTP-s-algo.htm#AEN2361
>
> - Stewart G3YSX
>
Hi Stewart es All,
I do some PC clock synchronizations via internet using the program
"Time Watch", downloaded from http://www.blue-series.de. the NTP server
transmitting the synchronization signals must be in your vicinity.
it is not usefull telling us that their timer is <1uS accurate 
(in my case dirived from GPS receivings) if there is a long wire to the
server. it`s something else if you would know the phase fault on the line 
and can correct it in some way.

reading the PC clock in mSec from the window "Time Decoder" of SpecLab
of one PC with the clock (motherboard and sound card) permanent 
synchronized by the standard time signal station DCF77 and at the 
same time reading the mSec from the screen of the other PC just 
clocking by the signals from the internet server, I believe I see
a difference, DCF77 in front.

be that as it may, we should reach an agreement about what kind of 
synchronization we will make use of.

there is a problem in synchronizing the PC clock by DCF77 (as with other 
standard time signal transmitters): During lf transmittings of your own 
station there will be no clocking because the DCF77 receiver will be 
overloaded (what is it in english "zugestopft"?).

if the program "Africam" will come into fashion agn (I played with it 
and the SD KIT abt 20 years ago) the case is`nt as critical as it sounds:
if I rember right there are two helpfull knobs, Autotrack and 
Aütofrequency.

BTW. if my station transmits all night long my neighbour runs 
into trouble with his employer: the radio alarm synchronized by DCF77 
doesnt wake him (the neighbour) up.

regards
Uwe/dj8wx