From: Gerhard Hickl <gerhard.hickl@aon.at>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Date: Mon, 11 Oct 2010 21:20:11 +0200
Message-ID: <1286824811.1513.18.camel@gerhard-desktop>
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Subject: LF: Locking SpecLab to 1pps
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Dear all!

Has anyone tried to lock SpecLab to a 1pps Signal yet?

The 1pps Signal is mentioned in the manual as a possible source for
calibration (as long as it has "low" jitter). In my job, I also have to
do with this kind of signal (we use it to synchronise Node B's) and as
far as I know, there's no specification about the duty cycle of such a
signal....so 1pps could be everything between 1% and 99% duty cycle but
usually it's constant. (=low jitter)

The idea is to derive the 1pps from DCF77. I know the 59th pulse is
missing at the end of every minute but this can't be the problem.
Because DCF77 is transmitting long and short pulses ("0" and "1"),  I
wonder if SpecLab will cope with this signal because it has rather high
jitter.

If so, it would be cheaper and more reliable than deriving the 1pps from
the GPS-system. At least I would like this way better.

Any experience on that?

73 es tnx

OE3GHB
Gerhard