Aircraft reflections (again!)

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G3ZOD
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Joined: 2009/04/18 - 12:39
Aircraft reflections (again!)
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I see there have been a couple of discussions about aircraft reflections in the past. However, yesterday I grabbed a snapshot that I think is showing this effect more dramatically than the other snapshots (be interested to hear if people agree that it is aircraft reflections).

I'm about 5 miles from the busy Manchester Airport and above this general area a number of airways meet, so it's quite a hotspot for aircraft.

The first WSPR snapshot is from a 6m station to the SW of me who has a permanently readable signal of around -10dB in WSPR (quite audible - would be an easy CW contact). However, my antenna is a dipole in an upstairs bedroom in a heavily built-up area; I guess this means that I get the reflections at good strength compared to the "real" signal.

I notice that the signals are nearly all decreasing in frequency.

The second SpecJT snapshot is from a CW station to the SSE of me who is also permanently about the same strength as the other station and this time the tendency is for signals to increase in frequency. I'm still trying to wrap my head around the geometry involved here.