[time-nuts] ARRL FMT results

Magnus Danielson cfmd at bredband.net
Thu Jan 4 08:15:07 EST 2007


From: "Poul-Henning Kamp" <phk at phk.freebsd.dk>
Subject: Re: [time-nuts] ARRL FMT results
Date: Thu, 04 Jan 2007 12:05:54 +0000
Message-ID: <33566.1167912354 at critter.freebsd.dk>

> In message <20070104.044145.1474621952.imp at bsdimp.com>, "M. Warner Losh" writes
> :
> >I have a silly question about these measurements...
> >
> >Since the signal is being transmitted from a fixed point.  Wouldn't
> >people west of the transmitter measure a different (lower?) frequency
> >than those east of the transmitter due to the rotation of the earth?
> >Or are those effect well below the margin of error that people have
> >reported measuring?
> 
> 
> You're a couple of hundred years behind on physics Warner :-)
> 
> Speed of light is constant, so as long as transmitter and receiver
> does not move relative to each other, the frequency stays the same.
> 
> But there will be a correction for their relative height in the
> gravity field (as shown by Toms mountain excursion).

However, if the signal "bounces" on an "object" moving towards or from the
receiver there will be a doppler effect. This is used in radar for instance.

Cheers,
Magnus



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