Category Archives: Aircraft Scatter

AirScout: New Version 1.1.0.0 is online!

February 10th, 2015

A brand new version of AirScout can be download. Frank, DL2ALF, has implemented a new source for airplane data as well as a couple of new features.

2015-02-10 20_12_49-AirScout - Aircraft Scatter Prediction V1.1.0.0 (c) 2013 DL2ALFMost spectacular is the ability to track airplanes with the antenna in azimuth and elevation. When enabling tracking, the user can select between several interfaces. I am using the plain WSJT-compatible “azel.dat” file. First tests on DB0NCO are very promising.

Presentation “Reflections on Air- and Spacecrafts”

January 15th, 2015Banner GHz-Tagung 2015On February 21st, 2015 Jan, PA3FXB, and I will give a lecture in Dorsten at the GHz convention. It will be held in german and partly in english and is basing on the former lectures “Let´s Bounce”.

We will talk about unusual use of Aircraft Scatter and our experiences using ISCAT. Two years ago the idea, to try ISS Bounce, was born and discussed in Dorsten. We will show what we have done in the meantime in practising this propagation mode.

A big Dish, a big Bird and a big Signal

January 6th, 2015

Jan, PA3FXB, and I skeduled a very special ISCAT test on 23 cm for today. The CAMRAS team had planned to operate PI9CAM with the 25 m radiotelescope in Dwingeloo for some astronomical experiments this afternoon. Before starting with that, we used an ISS pass with low elevation to try ISS bounce with the big dish. Such a pass ensures slow variation of azimuth end elevation angles, which is essential to track moving object like the ISS (or other spacecrafts in low orbits) with an antenna of a weight of 120 tons.

DSC_0384aWe had very strong reflections right from the beginning, but no decodes. Maybe the signal level was to high? This has to be investigated. Then we changed to aircraft scatter, although the dish had to be kept elevated at 10° by safety reasons, I got strong reflections from airplanes quite close to PI9CAM. Not as strong as from the ISS, but decodable now and it was possible to work in CW too.

Despite the fact, we had no QSO via ISS bounce, we learnt, that it is possible to track objects in low orbits with the 25 m radiotelescope, as long as the elevation keeps low. This opens up a perspective to make use of other spacecrafts as reflectors.

ISCAT – a new experience

January 3rd, 2015

Inspired by an article, published by Rex, VK7MO, and David, VK3HZ, in the latest DUBUS [1], Ronald, ON7FLY, and I performed a first test in using ISCAT-B mode (by K1JT) for aircraft scatter on 23 cm. When looking on AirScout it doesn´t seem to be very challenging to have an QSO. But Ronald is obstructed by a hill in eastern directions and he didn´t expect to have an opportunity to work eastwards on 23 cm at all.

2014-12-27 16_37_03-AirScout - ON7FLYRonald is located in JO10LT and the distance is just 388 km. He uses a 44 element yagi with only 2 W at the feedpoint. On my side a 3 m dish and 150 W are in use. First of all we tried in SSB and were able to complete a QSO after a while. I could copy ON7FLY very weak, but readable. Then we tried in ISCAT-B with 30 seconds periods and it was amazing to see, that Ronald´s signal could be decoded even when only traces appeared in the spectrum.

2015-01-02 15_28_46-His signal can be seen in the center section (The drop outs are reactions of the AGC on radar noise). The above sequence could be decoded to:

2015-01-02 15_29_22-Since the periods of 30 seconds were far too long, we needed certain airplanes to complete. then we tried FSK441 with no decodes and switched to JT6M and completed the third QSO. In the meantime I found a hint in the above mentioned article, how to reduce the T/R periods to 15 seconds. So we completed a fourth QSO in ISCAT-B again in shortest time: 2015-01-02 18_02_00-

 

[1] Rex Moncur, VK7MO, David Smith, VK3HZ, Aircraft Scatter on 10 and 24 GHz using ISCAT: DUBUS Vol. 43 4/2014

Presentation “Let´s Bounce” IIa

October 21st, 2014

Last night, when I was going to switch off all the stuff in my shack, I saw an email from Malte, DE7LMS. I opened it and found a link to a video he recorded of my recent presentation in Weinheim.

Presentation “Let´s Bounce” III

My presentation “Let´s Bounce” will be given on two more dates:

October 25th, 2014 on the 4th Hessian GHz Meeting in Fernwald

Short version of the lecture with focus on aircraft scatter and ISS bounce.
We meet at 15:00 MEST on the car park at the town hall. There will be a flee market for GHz stuff and the opportunity to test own equipment or to have QSOs with other participants.

Gaststätte “Ratsschänke”
Oppenröder Strasse 1, 35463 Fernwald-Steinbach
Locator: JO40JN33VG

November 7th, 2014, 20:00 MET on the monthly meeting of DARC OV Miltenberg, B24

Full Version with overview of propagation modes, aircraft scatter, ISS bounce and visual moonbounce.

Deutscher Amateur Radio Club e.V.
Ortsverband Miltenberg, B24
Gasthaus “Goldenes Faß”
Kirchstraße 13, 63920 Großheubach
Locator: JN49OR64JJ

If you like to attend or need further information, just send an email to dj5ar (at) darc.de

Presentation “Let´s Bounce” II

September 1st, 2014

ISS Bounce Title

After giving the presentation in english language in Clonbur, Ireland on August 25th, there will be two more dates in Germany:

September 13th, 2014 at the VHF/UHF/SHF Convention in Weinheim as a short version.

September 27th, 2014 at the “Distriktsservicetag” of DARC districts K (Rhineland-Palatine) and Q (Saarland) in Saarbrücken.

I will talk about how to surmount the horizon on VHF and up.

After giving an overview over the classic propagation modes Es, Aurora, MS and Tropo, I will explain, how aircraft scatter and ISS bounce work. EME will be subjected too and the presentation will be completed by an introduction to “Visual Moonbounce” as performed by Daniela de Paulis.

For the short version in Weinheim the overview over the classic propagation modes will be left out.

Presentation “Let´s Bounce”

June 22nd, 2014

On July 24th, 2014 on 19:00 CEST I will talk about how to surmount the horizon on VHF and up at the local DARC Club in Bodenheim near Mainz.

After giving an overview over the classic propagation modes Es, Aurora, MS and Tropo, I will explain, how aircraft scatter and ISS bounce work. EME will be subjected too and the presentation will be completed by an introduction to “Visual Moonbounce” as performed by Daniela de Paulis.

Location:
Deutscher Amateur-Radio-Club e.V.
Ortsverband Bodenheim
Haus der Vereine
Laubenheimer Str. 22
55294 Bodenheim

The admission is free, but please register via email to
DK2FQ   wolfgang.beer (at) gmx.net   or to me   dj5ar (at) darc.de

NAC/IAC in March

March 26th, 2014

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.