LF: TA Mar 4, CFH ripples

[MarkusVester@aol.com]

Dear Group,

in the waterhole, XGJ and XKO were reasonably strong here between 3:00 and 6:30, NA sporadically but much weaker than usual.

However nil WOLF copy from XES on 137577 Hz. I do have a weak unid line on 137580 (0.6 µV/m on groundwave, direction Frankfurt) which may have been a problem, even with it's power spread over 10 Hz.

There was very pronounced selective directional fading on CFH last night, with characteristics similar to those observed on SXV on Feb 10/11. The colour strips were spaced by about 60 to 90 Hz, indicating a 16 to 11ms delayed skywave component (!). The banding structure was first visible at 3:30 with abt. 0.06 Hz receding Doppler (ie. downward sloping ripples), went through near stationary at 4:10 (see screenshot) and ended around 5:30 at 0.11 Hz approaching.



Grabber image scales are 1.5 s and 5 Hz per pixel. Earlier last night between 22:40 and 23:30, weaker ripples were noticed on SXV as well. I would be very interested to know if anybody else noticed such selective fading characteristics on any of the "wideband" LF signals.

73 and best of luck

Markus, DF6NM