Tom,
For this to be true, you need to have equal tracking for each vehicle
so
that
you integrate equal amount of positive and negative shifts from each
vehicle.
Better yeat is naturally to compensate each measure for the mainpart
of
the
Sagnac effect. If you know it is there,
From: Tom Van Baak [EMAIL PROTECTED]
Subject: Re: ARRL FMT results
Date: Fri, 5 Jan 2007 10:26:37 -0800
Message-ID: [EMAIL PROTECTED]
Magnus,
Tom,
OK, let me rephrase what I meant - yes, the FMT
transmissions do experience a Sagnac effect (a
time synchronization propagation delay), as would
The other reason the SR and GR corrections must
be made in the SV is because they affect the GPS
clock frequency; it's a redshift.
Indeed. The SV is actually slightly low in frequency before lauch, it is set
to
-4.467E-10 below the nominal correct frequency to compensate the
You could do a simple test:
With an ohmmeter, on Diode test and with reversed
polarity (Red on shield, black on center pin), measure
the DC resistance on the RF connector. If it's a short
( 1 ohm) DO NOT APPLY ANY VOLTAGE ON IT! Your antenna
is passive and conducting.
If the ohmmeter indicates a
It turns out to be rather small, about 200 ns for a
full 40 000 km around-the-earth trip at the equator.
Actually, 207 ns. :-)
Magnus,
Yes, right. Let me take this opportunity to show
where that number comes from. For equatorial
circumnavigation the total Sagnac effect is:
T = -omega
Hi Norman,
Thanks for you very complete check out information. It
worked! The antenna is an active type with a preamp. I also hooked
it up to a VLF receiver and found it receives very well from near DC
to 100khz. No obvious peak at 60khz.
Thanks again,
Doug
