Last night I have been active in the Nordic and Italian Activity Contests on 13 cm. The conditions were awesome. Just four QSOs with IK2OFO (JN45), IZ4BEH (JN54, new #), DL0VV (JO64) and OZ3ZW (JO54) were written to the log, very weak Signals and rare airplane reflections most of the time. So it needed much patience and certain aircrafts to complete the QSOs as the audio record of my QSO with Roberto, IZ4BEH, shows.
It demonstrates my style of operation in aircraft scatter QSOs. I keep the transmissions short and listen in between. Only relevant information will be sent, because the duration of a reflection is typically very short. Fixed periods in aircraft scatter tests are not required at all. The first signals, received from Roberto, included the callsigns and fractions of a report. So I could be sure, that both calls were exchanged and only the report was needed. The locator was sent too, because IZ4BEH has been working in the Italian Activity Contest. It took quite a while, until a second airplane passed by near the midpoint of the path, giving us the chance to complete the QSO.
After my recent complainment about the challenge of the chat in March Contest, I got emails from Claus, OZ1FDH, and Kjeld, OZ1FF, with information about KST2ME, a tool to manage the ON4KST chat. I made use of it in the activity contests and it is a real improvement compared to the pure webclient. Thank you, Claus and Kjeld, for the feedback! KST2ME can be downloaded from Bo´s, OZ2M, homepage.
Frank, DL2ALF has written an amazing tool for aircraft scatter prediction, called AirScout. Positions of planes are shown in a map like at http://planefinder.net or http://www.flightradar24.com, but in addition the path and the part of it, where planes could be seen from both stations will be marked. Frank is using open street map for the maps and an elevation model of NOAA to respect the topography of the path. I made use of a beta version last Tuesday in the NAC on 23 cm and found it extremly helpful.
As can be seen in the screenshot, the effective area is excentric to the center of the path. It is displaced southwards because IK3HHGs horizon is limited by the alps.
Eight times IK3HHG shifted by doppler, corresponding to the screenshot above
Last saturday at the GHz meeting in Dorsten Frank told me, that he integrated the groundtrack of the International Space Station to be drawn in the map too. So we have been discussing about the possibility of performing QSOs via reflections at the ISS.
AirScout with groundtrack of ISS
Back home I was very optimistic and used overflights, where the ISS passed by nort of my location to look out for reflections of GB3MHL on 23 cm, but had no success. There was no trace at all in the waterfall diagram of my SDR. The duration of a pass is only up to 9 minutes and the expected doppler shift is +/- 84 kHz due to the high speed of 28000 km/h. So even if something could be heared or seen, tracking and decoding the signal will be another problem to be resolved.
But anyway: I am looking for somebody to perform tests with me, just to detect reflections at the ISS. Skeds are welcome via chat (ON4KST and HB9Q) or email dj5ar (at) darc.de
The Nordic Activity Contest is always a very good opportunity to work . . . Italians!
Tonight everything was upside down. After loosing John, G3XDY in QSB – a fact that is very, very strange – I wanted to turn the dish via south to north, when Sergio, I1KFH was meeping me. We tried and had our QSO in SSB. What else to say? Giorgio, IK3GHY followed as well as Robert, IZ4BEH and Frank, IK3HHG and Walter, IW2BNA and finally Roberto, IK2OFO.