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From: Mills@udel.edu
Newsgroups: comp.protocols.time.ntp
Subject: Re:  Cheap Radio Clocks (was Re: CTS-10 PC clock board)
Message-ID: <9010061259.aa27989@huey.udel.edu>
Date: 6 Oct 90 16:59:35 GMT
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Philip,

Well, remember Rugby is not as far from most places in the UK as Ft. Collins
is from most places in the US. The secret to the Spectracom WWVB receiver
success is undoubtably the very narrow crystal filter just after the RF
stage, which nicely kills the 63-kHz harmonic of the TV sweep frequency used
in the US. The result is that 100-microsecond accuracy is not hard to achieve.
In spite of that, your 700-microsecond variance still sounds too large to
account for in the receiver, suggesting maybe much of that is due to the
computer interface and interrupt latencies.

I surely can't argue that your interface is anything but inexpensive!

Dave