LF: MSF Oddities

[Andy Talbot <andy.g4jnt@gmail.com>]

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