144 mhz beacons and aircraft scatter

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Listening 144 MHz beacons and Aircraft scatter

 

After the repair of my antenna system for 144 MHz I decided to do some search for beacons which I can copy.

I did this before but not very successful. Then I only heard PI7CIS which now is QRT

Now with some more time and using better reference I found several beacons which I can copy most of the time.

CALLSIGN FREQUENCY HEADING LOCATOR DISTANCE
F1ZXK 144.437 210 degrees JN18AS 583 km
F5ZAM 133.425 240 degrees JO10EQ 421 km
DB0FGB 144.444

132 degrees

JO50WB 420 km
DB0MMO 144.455 156 degrees JN49RV 337 km
DM0HVL 144.450 94 degrees JO62KI 364 km
OZ1FYR 144.483 18 degrees JO45QU 372 km
ON0VHF 144.418 223 degreesJ JO20HP 304 km
DM0PR 144.486 24 degrees JO44JH 199 km
PI7HVN 144.423 285 degrees JO22WW 116 km
DB0OHZ 144.440 54 degrees JO43JF 103 km
         
         

I was surprised by this good result and noticed that the ODX beacon F1ZXK was audible very often.

I never expected that Aircraft scatter would work very well on 144 MHz but by listening to F1ZXK I started to realize that this was aircraft scatter.

The scatter area seems to be in a major airway
 I hear the beacon between 40 and 60 % of time. Signal strength varying between just audible up to 20 dB S/N

I made a longer measurement using Dopplegram to see the different received signals from the beacon.

This is a 10 minutes registration, in this period we see at least 6 aircraft causing reflection

This is a registration of 70 minutes with many aircraft, you can also see the drift of my LO.

When there are no aircraft in the scatter circle I don't receive the beacon.

It is clear that aircraft scatter is also very important for 144 MHz.