The plot below and also to be found at http://www.g4jnt.com/DropF/clipboard_201803301751.png shows the phase and amplitude of the MSF 60kHz signal received here on the south coast over a period of
It is reasonable for it to be a genuine change of phase as the solar zenith angle varies through the day and D-region ionisation varies with it. For comparison I attach a plot of GBZ (distance 155km)
http://www.g4jnt.com/DropF/clipboard_201803301751.png shows the phase and amplitude of the MSF 60kHz signal received here on the south coast over a period of 5 hours. Whilst I would expect phase c