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Date: Sun, 8 Nov 2015 19:08:23 +0000
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From: Andy Talbot <andy.g4jnt@gmail.com>
To: rsgb_lf_group@blacksheep.org, rsgb_lf_group@yahoogroups.co.uk
Subject: LF: MSF Oddities
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I've been using the MSF 60khz signal as a test source for cohernet LF Rx
development.   And in doign so I've noticed a couple of oddities

First was tonight, see http://www.g4jnt.com/DownLoad/MSF_Log2.jpg   where
it appears to have dropped for a few minutes round about 1715z.  I didn't
catch this in real time to check and only saw the plot afterwards, but fail
to see how that could be a software glitch that recovered so perfectly
afterwards.

Also note the reduction in power around 1800.   I spotted this yesterday
too - and that was confirmed by listening on another receiver.  The signal
really was several dB weaker after, AFAIR, about 1800 ish.    So it looks
as if they may drop the power after dark when propagation is expected to be
at its best.

Once again, blame the VE2ZAZ GPSDO for the phase shift of something like 40
degrees over 2 hours.  That  corresponds to only 2.5* 10^-10 at 60kHz , but
is very noticeable on plots such as this.

Andy  G4JNT

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<div dir=3D"ltr">I&#39;ve been using the MSF 60khz signal as a test source =
for cohernet LF Rx development. =C2=A0 And in doign so I&#39;ve noticed a c=
ouple of oddities<div><br></div><div>First was tonight, see=C2=A0<a href=3D=
"http://www.g4jnt.com/DownLoad/MSF_Log2.jpg">http://www.g4jnt.com/DownLoad/=
MSF_Log2.jpg</a> =C2=A0 where it appears to have dropped for a few minutes =
round about 1715z.=C2=A0 I didn&#39;t catch this in real time to check and =
only saw the plot afterwards, but fail to see how that could be a software =
glitch that recovered so perfectly afterwards.</div><div><br></div><div>Als=
o note the reduction in power around 1800. =C2=A0 I spotted this yesterday =
too - and that was confirmed by listening on another receiver.=C2=A0 The si=
gnal really was several dB weaker after, AFAIR, about 1800 ish. =C2=A0 =C2=
=A0So it looks as if they may drop the power after dark when propagation is=
 expected to be at its best.</div><div><br></div><div>Once again, blame the=
 VE2ZAZ GPSDO for the phase shift of something like 40 degrees over 2 hours=
.=C2=A0 That =C2=A0corresponds to only 2.5* 10^-10 at 60kHz , but is very n=
oticeable on plots such as this.</div><div><br></div><div>Andy =C2=A0G4JNT<=
/div></div>

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