Category Archives: Propagation

Tropo to Belarus this Morning on 144 MHz

September 9th, 2020

A nice inversion could be seen out of the window of my shack this morning, promising good conditions. In fact I have been a little too far south for the duct, but at least I had two QSOs to Belarus in FT8.

Green: worked – Red: heard via tropo – Blue: heard via meteor scatter

The stations worked and heard via tropo have been in distances up to 1300 km. Occasionally signals appeared from more distant stations, 1500 and more km away. These could be decoded in one or two periods, then disappeared. Some reappeared later in the same manner, so it´s very likely it has been meteor scatter, as it happened in the early morning, when conditions are good for sporadic meteors.

Worked Hrd Tropo Hrd MS 

New Bands down to DC

May 7th, 2020

Yesterday I added a logarithmic periodic antenna for the range 28 to 150 MHz to my little antenna farm. So I am QRV now on the amateur bands from the highest DC band 28 MHz up to 2400 MHz.

Antennas at DJ5AR

Recently I got an IC-7300 with extended frequency range to cover the 50 MHz and 70 MHz, as well as the new Irish bands 80 MHz and 60 MHz.

So I am looking forward to have some cross band QSOs to Ireland soon!

I took down the 3 cm dish for some work on the rig. And I know, the 70 cm yagi is much too close to the new antenna, but I have been too lazy to dismount it.

Addendum May 18th, 2020

First PI4 decodes of EI1KNH in IO63VE on 40 MHz.

AirScout V1.3.3.0 released

May 3rd, 2020

The VHF/UHF/SHF contest on 2nd to 3rd of May was a good opportunity to spend a few hours trying the new AirScout version released by Frank, DL2ALF. In principle it works like it´s predecessors, but is more stable in collecting the aircraft data. My favourite in this case is

Most impressed I am by the new feature to monitor a number of paths to certain stations simultaneously! This provides more efficiency in arranging skeds, particularly in times like these, when there are a few planes only are available.

Find more details on the AirScout Site.

Strange Conditions Today

January 1st, 2020

I got up quite early today and decided to check the beacons on 23 cm. When beaming to LA1UHG, there was a noticeable signal in F1 about 1 kHz above its frequency. It was easy to read it as DB0LB from the back of the dish. But it seemed, there was another faint signal right beside the spacing carrier. With the help of my SDR radio I could set very narrow filters and after a while of listening, I identified it as LA1UHG, JO59FB, 1028 km. Wow!

But the signal faded out more and more and at least it disappeared.

LA1UHG just 140 Hz below the space carrier of DB0LB

Later this morning, the dish still pointing north, I heard Kurt, OE5XBL, chatting in SSB with Rudi, OE5VRL/5, both with very strong signals on 23 cm. Expecting a huge signal, I turned the antenna to Kurt, but there was no significant increase in signal strength. I called in and the three of us were talking about the conditions and to meet for a beer at the GHz convention in Dorsten next February, when Kurt was called by Dave, G4RQI. I had tried with him earlier without any success, and so, to be honest, I was a little annoyed by this. Even, when turning the dish to the UK, I couldn´t copy anything of Dave’s transmissions, while he was working Kurt and Rudi. These were enough indications, that the inversion was at a too high altitude for me, to enter it. So I went for a long walk with my XYL in the nearby vineyards.

The inversion is at an altitude of about 1000 m (Courtesy DWD)

In the evening I performed another beacon check. It was funny to see beacons, the dish was pointing to, as well as others from the back of the dish

Dish pointing southeast: DB0UX, DB0VC, DB0AAT (from left to right)

Turning the dish, confirmed the experience I had in the the morning: Pointing southeast I saw DB0VC, JO54IF, next to DB0AAT, JN67HU. Turning the dish towards Kiel in the north, the signal of DB0VC increased just a little. Maybe, it has been reflected by a mountain range about 50 km southeast of me.

Dish pointing north: DB0UX, DB0XY, DB0VC, OZ7IGY (from left to right)

F5ZNI: Beacon #34 on 13 cm

December 29th, 2019

By performing my daily beacon check, I noticed a weak keyed carrier in between the spacing of the F1 signal of DB0UX on 2320.900 MHz. I assumed to see F6DWG/B, which I monitored around the .900 before. But it didn´t take long to find out, that the real signal (mark) was the lower carrier and after a while I learned, it was F5ZNI using reverse F1 keying. Later in the evening the signal increased due to good tropo conditions, as can be seen in the pictures. F5ZNI is the 34th beacon I received in the 13 cm (S) Band

F5ZNI and DB0UX in PowerSDR

I am always happy about new beacons, but this case is an example, why beacon coordination and using standards is most important. First of all, reverse F1 keying is always bad, as you are used to listen to the upper carrier of the signal. In case there is an unkeyed carrier in between the text, you can easily identify the mark, where to listen. But if there is text keyed nearly all the time, as F5ZNI does, it is rather time consuming until the mark is identified.

The DB0UX signal was strong and the frequency is locked to a reference, while F5ZNI is drifting a little. So it was obvious, that there was a second signal in place. If the french beacon would have been locked to 2320.900 MHz too and would use the standard A1 or F1 keying, there would have been no chance for me to monitor or even to take notice of it.

An excerpt from BEACONSPOT.UK shows the situation on 2320.900 MHz:

BeaconNominal FrequencyLocatorLast SpottedLast FrequencyStatus
OZ5SHF2320.900JO45VX2019-08-242320.900Operational on spot date
DB0UX2320.900JN48FX2019-12-292320.900Operational on spot date
F1ZCC2320.900JN08XSUncertain - new spot required
F5ZNI2320.904JN19BQ2019-12-302320.899Operational on spot date

Depending on the location and the conditions, there will be more or less interference on 230.900 MHz

So I am urging all beacon keepers to make use of the service provided by the
IARU R1 VHF/UHF/MW Beacon Coordinator. When designing a beacon, please respect chapter 11 “Beacon Requirements” in the IARU-R1 VHF Handbook.

DB0XY back on Air

December 17th, 2019

As the beacon keeper Thomas, DL4EAU, wrote me, the DB0XY beacons in JO51EU are back on air. The frequencies are 1296.912, 2320.912 and 10368.912 MHz. All are locked to a GPS reference now.

DB0XY on 1296.912 MHz in JN49CV: A weak tropo trace, but many nice reflections on airplanes
DB0XY on 2320.912 MHz: No trace via tropo, but many reflections on planes

Moon Bounce out of the Boot

September 28th, 2019

On the annual service day of the DARC districts Saarland and Rhineland-Palatinate I had the pleasure to hold a lecture about EME basics and how to get into. Afterwards I invited the audience to try a live moon bounce QSO on 432 MHz from the parking lot outside. I had prepared some standard equipment of the kind, many might have in their shacks:

  • Transceiver Yaesu FT-897
  • 15-Element Yagi (YU7EF )
  • PA Gemini 70, ca. 200 W
  • LNA SHF-Elektronik, 0,8 dB NF
EME rig in the boot, Photo by courtesy of Klaus, DF6WN

Unfortunately it was rainy outside, the moon close to the sun and a G2 solar storm in progress. When swithing on the transceiver, I noticed some quite massive local QRM. Nevertheless I contacted Bernd, DL7APV, who had agreed in a sked, by phone, to tell him about the noise and that we were ready to go.

Bernd´s array of 128 x 11 elemnt yagis during a barbeque last June

As the noise level went up and down and Bernd is one of the big guns on 70 cm, we were able to decode most of his transmissions despite all adversities. Finally we completed the QSO. That was a great job, Bernd!

I enjoyed to be in Saarbrücken and would like to say thank you to Eugen, DK8VR and his team for organising DST 2019!

F1ZBK in JN38BP back on air on 1296.854 MHz

June 7th, 2019
Doppler shifted traces (1000 Hz = 1296.854 MHz)

When looking for EA2TZ/B during a beacon check a couple of days ago, I mentioned a signal with strong doppler shift about a khz below. As I like the challenge to identify new beacons, I started monitoring it. It became a kind of a nightmare, trying to to catch the beacons callsign. It seems to be very chatty, transmitting a whole bunch of unuseful text. despite the fact I got a lot of good quality fragments via aircraft scatter, it took me hours to identify it as F1ZBK. At least I am pretty sure it is, as there is a second callsign in the end of the text: F1DND, maybe it´s the keepers call.

The text decoded so far is:
—— beacon f1zbk jn38bp nancy … 854 khz … 5 watt … f1dnd … orange KA … ——-
Where the “…” represent gaps and KA is the prosign for “Attention” or “New Message” (not to be used at the end of a message, like AR).

There are many beacons running in bad modes like reversed F2A or keying the subcarrier of F2A, but transmitting such a lot of stuff is worse.

It would be a great advantage, if all beacon keepers will respect the beacon requirements as published in the VHF Handbook of IARU R1.

OK0ER via Aircraft Scatter on 13 cm

October 22nd, 2018

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.


Weltraumkinder schicken Astro-Alex zum Mond (German)

August 2018

Großes Finale im Weltraum-Projekt zum Ende des Kindergartenjahres!

Seit dem Auftakt mit einer Mondbeobachtung an der Paul-Baumann-Sternwarte der Astronomischen Arbeitsgemeinschaft Mainz e.V. im April konnten die Kinder viele Eindrücke vom Weltraum und dem Leben der Astronauten auf der Internationalen Raumstation sammeln. Sie absolvierten ein Raumfahrer-Training und stellten selber Astronauten-Nahrung her. Es wurde der Flug von Alexander Gerst zur ISS verfolgt und eigene Brausepulver-Raketen gestartet. Warum Funkverbindungen hinter den Horizont schwierig sind, konnte mit Walkie-Talkies selbst ausprobiert werden. Und nicht zuletzt war dann Astro-Alex selbst live per Amateurfunk von der Raumstation zu hören, als er Fragen von Schülern von Schulen in Leverkusen und Herrenberg beantwortete.

Bild: Alexander fliegt zum Mond (Ben Brinkhus)

Da der Mond ein erklärtes Ziel von Alexander Gerst ist, haben die Kinder dann Bilder gestaltet, die ihn auf dem Weg zum Mond zeigen. In Interviews erzählt er gern von seinem Opa, der als Radioamateur Funksignale am Mond reflektieren lassen konnte, was den jungen Alexander seinerzeit immens beindruckt hat. Deshalb wurde eins der Bilder ausgewählt und zusammen mit einem Foto von ihm, seinem Missions-Logo und dem Logo der Kindertagesstätte St. Laurentius ging es auf die Reise nach Italien zu Nando Pellegrini, der als Funkamateur unter dem Rufzeichen I1NDP eine große Sendestation betreibt. Mit seinem Parabolspiegel, der einen Durchmesser von 10 m hat, sendete er die Bilder im 23 cm Amateurfunk-Band im sogenannten Slow-Scan-Television-Verfahren, ähnlich einem FAX, in Richtung Mond. An der Oberfläche unseres Trabanten wurde die Funksignale reflektiert und trafen zweieinhalb Sekunden später mit Lichtgeschwindigkeit wieder auf der Erde ein.

Bild: Radioteleskop in Dwingeloo

Hier hatte sich das historische Radioteleskop in Dwingeloo in den Niederlanden bereitgehalten, um die Bilder nach ihrer Reise über fast 800.000 km wieder aufzufangen.Betrieben wird die denkmalgeschützte Einrichtung in der Provinz Drenthe im Nordosten der Niederlande von der CAMRAS Stiftung, in der eine große Zahl von Funkamateuren mitarbeitet. Hier, an der erst vor fünf Jahren aufwändig restaurierten Parabolantenne von 25 m Durchmesser, haben die italienische Künstlerin Daniela de Paulis und der niederländische Funkamateur Jan van Muijlwijk, Rufzeichen PA3FXB, im Jahr 2009 das „Visual Moonbounce“ genannte Verfahren entwickelt, bei dem sie im Rahmen von Kunst-Projekten und Astronomie-Events der „Astronomers without Borders“ mit Hilfe geeigneter Gegenstationen in Italien, Brasilien, Großbritannien und der Schweiz Bilder am Mond reflektiert lassen.

Dank guter persönlicher Kontakte konnten die beteiligten Funkamateure dafür gewonnen werden, die Bilder der Ebersheimer Weltraumkinder im Rahmen einer öffentlichen Veranstaltung in Dwingeloo zum Mond zu schicken, um den dortigen Besuchern „Visual Moonbounce” eindrucksvoll zu demonstrieren.

Bild: Alexander Gerst (ESA)

So kam es, dass nicht die ESA, sondern die Weltraumkinder der Kindertagesstätte St. Laurentius in Mainz-Ebersheim Alexander Gerst zum Mond geschickt haben.Wir danken Daniela de Paulis, Jan van Muijlwijk, Nando Pellegrini sowie dem Team CAMRAS für die Unterstützung unseres Weltraum-Projekts! Das Bild vom Flug zum Mond hat das Weltraumkind Ben Brinkhus gestaltet.

Ansprechpartner für das Weltraum-Projekt: Regina Imse,
Kath. Kindertagesstätte St. Laurentius, Großgewann 2,
55129 Mainz-Ebersheim

Zeichnung „Alexander fliegt zum Mond“: Ben Brinkhus
Alexander Gerst, Horizons-Logo: ESA
Radioteleskop Dwingeloo: Andreas Imse
Logo der Kindertagestätte St. Laurentius, Mainz-Ebersheim
Reflektierte Bilder: Nando Pellegrini und Team CAMRAS