As OK0EA was audible this morning on 23 and 13 cm I had a look for other, more distant beacons in OK. After noticing a very short and weak signal on 2320.9085 MHz, I monitored the frequency over a couple of hours and saw many doppler shifted traces, typical for aircraft scatter. Very soon I copied “…9DP…”, when a B777 crossed the path and was sure to see OK0ER in JN99DP in the waterfall diagram. At least 4 Airbuses A380 crossed the path one after the other, giving nice reflections.
OK0ER transmits 1.5 W into a slot antenna in 675 m asl. The distance is 722 km.
As I digged a little deeper, I learned, the source of the signal on 2275,225 is not Queqiao, but it is it´s companion Longjiang-2 or DSLWP-B in an orbit around the moon.
August 23rd, 2018
Designed as a relay for the planned chinese Chang’e 4 misson to explore the far side of the Moon with a lander and a rover, the Queqiao probe has reached it´s final destination 60000 km behind the Moon. There it is in a halo orbit with a radius of 15000 km around the Langrangian L2 point of the Earth-Moon-system. So it won´t be covered by the Moon, seen from Earth.
Queqiao also carries a radio astronomy experiment for low frequency exploration in collaboration with dutch ASTRON. After the lainch in May 2018 two microsatellites Longjiang-1 (DSLWP-A) and Longjiang-2 (DSLWP-B) were released, to enter orbits around the moon. These satellites carry a radio astronomy experiment as well as amateur radio payloads. While Longjiang-1 went lost, Longjiang-2 is operating and can be monitored in the 70 cm band as well as in the S-Band.
The signal of the S-band beacon is audible at about 2275.225 MHz. The used equipment is HDSDR software with a RTL-SDR-Stick connected to a 13 cm ATV Converter (LO=916 MHz) and a 13 cm LNA (Kuhne) at a 23/13cm dualband ringfeed in my 3 m dish.
After I noticed some spots for SR1KOL in JO74SE on 1296.960 MHz, I monitored the frequency using WSJT-X Wide Graph. About 400 Hz below the nominal frequency traces of a F1 signal can be seen, when airplanes cross the path to the beacon. The signal is not audible, but I am pretty sure, it is SR1KOL.
Traces of SR1KOL in JO74SE, “1000” = 1296.960 MHz. The strong signal at the very left is a birdie.
Some information can be found on the website of Polski Klub UKF: It is located on a high rise building in Kołobrzeg, 40 m above ground. The power is 3 W into a slot antenna. Beacon keeper is Andrzej, SQ1GU.
The video shows an A380 crossing the path between DJ5AR and SR1KOL. At minute 2:00 the plane crosses the first time and at minute 4:00 after a turn it crosses a second time. Mind the traces at 580 Hz in the waterfall diagram. The 1000 Hz mark corresponds to 1296.960 MHz.
Irek, SP5MX, who was involved in building the beacon and who repaired it recently, told me, the beacons reference is an OCXO withtout any GPS-lock. So possibly the beacon may transmit 400 Hz lower than defined.
At least in the morning of July 31st audible reflections could be heard via an Airbus A330. This time the 1000 Hz mark correspondents to 1296.9596 MHz.
After 10 seconds the noise becomes a kind of ‘musical’. Another 10 seconds later experienced ears can hear the tone.
This morning I had a look for DB0MFI, a new beacon on 1296.940 MHz in JN58HW. It is audible with 529 constantly via tropo and peaking 579 via aircraft scatter. The power is 5 W into a 4 times stacked big wheel antenna.
In the afternoon I went for it on 2320.940 MHz. Faint reflections on some airplanes were audible and traces could be seen in the waterfall of WSJT-X Wide Graph:
The french beacon F5ZBM is on air again. I found it accidentally, when looking for other french beacons. It is at a new location in JN18MN near Paris transmitting on 1,296.8475 MHz. Nice to monitor it in Mainz via aircraft scatter over a distance of 406 km!
The keying is in F1 with a very narrow spacing. Power is 10 W ERP into a slot antenna, as can be seeen at BEACONSPOT.eu
Tonight I monitored OZ7IGY on 2,320.930 MHz via aircraft scatter. It was nice to see other beacons appearing shortly in the waterfall diagram.
OZ7IGY and friends in time lapse
From left to right:
2.320.900: DB0UX, JN48FX, 105 km, tropo
2,320.910: DB0XY, JN51EU, 263 km, aircraft scatter
2.320.920: DB0VC, JN54IF, 509 km, aircraft scatter
2,320.930: OZ7IGY, JN55WM, 670 km, aircraft scatter
The dish was bearing 20° to OZ7IGY. The -3 dB beamwidth is just 3.2° on 13 cm.
After installation of new transverters for 23 and 13 cm with stabilized LOs a couple of months ago. I gathered some experience in using JT65C mode on EME. So I undertook a new attempt to receive and decode G8MBU via aircraft scatter today. As antenna I use a 3 m dish with a dual band ringfeed.
Path DJ5AR to G8MBU
The beacon is located at Cowes on the Isle of Wight, IO91IR37, 683 km from Mainz, JN49CV. It runs 2 W power into an omnidirectional dual alford slot antenna. The mode used is JT65c. Nominal frequency is 1296.800 MHz. To successfully decode the signal, the SSB dial should be set to 1296.7986 MHz, to get a tuning tone of 1400 Hz in WSJT.
There is a small window between the Isle of Wight and Mainz, where high flying aircraft can be “seen” from either places. But only a few airplanes cross the path within and fewer fly along the path. Reflections of G8MBU could be seen from time to time, but mostly too weak and too short to provide decodes. It took nearly 3 hours until the first decode happened at -22 dB and just some minutes later a second one appeared on the display at -21 dB: