Category Archives: Allgemein

Tropospheric Ducting

June 3rd, 2023

In Spring 2022 I installed a new antenna system for 2 m, 70 cm and 23 cm at my second home in Ireland. In the last days I could experience an long duration tropospheric opening to the continent. On May 23rd I noticed a large ducting area to the north, shown in the Hepburn Tropo Index. Not really expecting something, I turned the antenna northwards and was surprised to hear OY6BEC in IP62mb over 958 km with 529 on 2 m. It could be monitored most of the time until June, 2nd. Even on 70 cm it could be heard from time to time, but nothing on 23 cm, even when it peaked up to S9+20 dB on May 28th. I contacted Regin, QY1R and Trygvi, QY4TN, for skeds on 2 m, but unfortunately no signals could be detected. The two stations are quite close to sea level and the beacon is located on Mt. Sornfelli, 745 m asl.

From May 13th to May 28th I had a couple of contacts in the range, aircraft scatter allows. Beside the 2 m QSOs (green), I had some on 70cm (blue) as well. I worked the local lads on 23 cm (red) and had a QSO with Martin, GM8IEM, as I had promised him to arrange a sked, as soon as 23 cm is up and running. On May 26th a short Es opening happend and I could work Paolo, IK7UXW, with whom I had a couple of QSOs and tests from home in Mainz on 23 and 13 cm via a combination of tropo and aircraft scatter propagation.

On June 29th the reach extended by tropo to the costal area from northern France to the west of Germany. ODX of the day was Günter, DG6JF/P, over 1105 km.

As the propagation conditions went to normal for me on May 30th, the next day, May 31st, startet with QSOs to Denmark on 2 m (green) and 70 cm (blue). Around noon the duct extended to the very north of Germany. ODX of the day was Oliver, DH8BQA, JN73ce over 1559 km. The duct seemed to be very narrow, as Chris, SM6VTZ, and Steffen, DD0VF, could only be worked via meteor scatter (yellow).

The duct moved southwards on June 1st with many stations from Belgium, the Netherlands and Germany. no more DX contacts were made on 70 cm, just the 2 m band was open for me. ODX of the day was Uwe, DL4DWA, over 1559 km, followed by Peter , DL3JIN over 1542 km.

And again the duct moved southwards on June 2nd and calmed down around noon. ODX of the day was Gerhard, DK1FG, over 1459 km with an outstanding signal, just, as I am used to, when QRV at home in Germany.

Fun fact: When I turned my antenna to the north in the early morning of June 2nd, OY6BEC over 980 km was still there. Turning the antenn to the east, I could hear DB0HRF, JO40ff, over 1276 km. It is located on the Feldberg, as close to my German home, that I can see the mountain out of the window of my shack.

FR5DN/B 144 MHz TEP Beacon on Reunion

February 6th, 2023

Phil, FR5DN, is running an experimental beacon on 144.245 MHz beaming to the eastern Mediterranean Sea. It is located on the island of Reunion in LG78qs. The antenna is a 13 dB yagi, horizontal polarized at 7 m above ground, running 80 W. He will operate it in CW, when he is at home, mainly from 16:00 to 18:30 UTC.
The operation will be announced on DX Summit and in the ON4KST chat. As he transmits continuously, feedback may be sent in the chat or via his email address on QRZ.com.

FR5DN/B beaming towards the Mediterranean Sea
The geomagnetic equator is shown in green

He already tried years ago, but got inspired by the TEP events that happened recently in South America and hopes for monitors in Europe to gather some experience in this propagation mode.

Nice Morning Inversion

August 2nd, 2022

As the Hepburn Tropo Index predicted some ducting over northern Germany and the Baltic Sea for todays morning, I checked the beacons on 23 cm. DB0VC, JO54if, 509 km, was strong on 23 cm as well as on 13 cm, but nothing on 3 cm. I went on with the OZ and LA beacons and found OZ5SHF, JO45vx, 685 km and LB2SHF, JO48ad,917 km, with booming signals. Unfortunately there was no one QRV in Scandinavia.

Then I called in FT8 on 2 m and got some response from Denmark and Northern Germany. Surprisingly I got called by UA2FBW, KO04ir, 1002 km and much more surprised I have been, when I saw in the DX cluster, that EA5GJ, JM97jw, spottet me as well at the time, I worked Igor. Might have received me by some Es or MS, while beaming northeast.

With the rising sun the beacon signals on 23 cm became weaker and weaker and disappereared at least. The same happened to the DX stations on 2 m.

QSOs on 2 m in green, all in FT8. Received beacons on 23 cm shown in red.

New Antenna System at EI8HH

June 4th, 2022

When going to Ireland in May, I went with a trailer and could take a pneumatic mast and some antenna stuff with me. So I setup a 2 x 7 elemt yagi for 2 m, a 15 element yagi for 70 cm and a 67 element yagi for 23 cm. The rotator is a Spid BIG-RAS/HR, so elevation is possible as well. There are SHF-Electronic LNAs at each antenna and Gemini linears with 200 to 300 W driven by an IC-9700.

On 2 m I could log a couple of QSOs in FT8 (blue) and SSB (green) so far and have been lucky to use some tropo to France on May 27th and 28th (F6DBI, IN88ij, 716 km and F8BON, IN86wv, 903 km) and Spain on May 28th (EC2BBS, IN93bi, 1262 km).

Aircraft Scatter Podcast

February 7th, 2022

Today I had a talk about Aircraft Scatter with Michael, OE1CMW, who recorded it to produce a podcast for his series “ON AIR – Amateurfunk D-A-CH“. As it´s in german language, I keep this post in german.

Heute habe ich mit Michael, OE1CMW, über Aircraft Scatter gesprochen. Michael hat das Gespräch für seine Podcast-Reihe “ON AIR – Amateurfunk D-A-CH” aufgezeichnet.

In meinem Blog finden sich viele Beispiele zu QSOs und Bakenbeobachtungen als Anregung für eigene Aktivitäten. Unter dem Menü-Punkt “Aircraft Scatter” habe ich die QSO-Prozedur ausführlich beschrieben. Das Programm AirScout von Frank, DL2ALF, gibt es als Download für das Betriebssystem Windows.

Hier als Beispiel ein QSO mit DJ5BV auf 23 cm. Man hört sehr schön die Änderung der Tonhöhe infolge des Doppler-Effekts und verschiedene Signaltöne durch Reflexionen an verschiedenen Flugzeugen.

Wenn man Baken beobachten will, sollte man WideGraph von WSJT-X mitlaufen lassen, dann kann man auch schwächste Signalspuren sichtbar machen und auch die Doppler-Verschiebung sehr gut visualisieren.

F5ZBM in Sendeart F1

DB0UX screwing in Waterfall

January 14th, 2022

F5ZNI on 13 cm in JN19BQ, 440 km away, is a good indicator for troposheric duting to the west. Drifting up and down, it is transmitting just a little below GPS locked DB0UX in JN48FX, just 105 km to the south.

This is, how it usually looks, when I monitor F5ZNI on about 2320.899 MHz. DB0UX to the right with space 800 Hz lower. F5ZNI about 1250 Hz lower with space 500 Hz up.

Tonight DB0UX appeared a little different, somehow screwing through the waterfall display.

What happened?

Well, there is a windmill in 500 m from my QTH a little north of the path to F5ZNI and the wind raised to blow with 6 km/h from NE ……

New Activity Contest for digital modes on 23 cm

December 21st, 2021

The QSO BANAT Association organizes FT8 Activity Contests every 1st and 2nd Wednesday each month on 2 m and 70 cm. From 2022 on they added a 23 cm Activity Contest on the 3rd Wednesday. In respect, that FT8 is not useful with propagation modes like aircraft scatter on this band due to the doppler effect, it is open for the use of ISCAT, JT65, JT6m, JT8f, JTMS and MSK144 as well.

OE5XHE: Hrd Beacon #72 on 23 cm

After decoding some HA stations in FT8 on 2m and my beacon check found strong signals from DB0AAT and OK0EB on 23 cm as well as from DB0SHF, DB0NCO andOK0EA on 13 cm, I had a closer look at that area. At least I found OE5XHE on 1296.975 in JN78DN24GJ, 1120 m asl. It ist transmitting in A1 with 2 x 3 W into two planar antennas (WIMO) with 9 dBD each. The antennas beam to 105° and 205°. The beacon keeper is Hans, OE5ANL. More information on QRZ.com

OE5XHE to the right on 1296.975 MHz, very weak on 1296.970 MHz a trace of OB0EB and on 1296.965 MHz DB0ANN.

23 cm Beacon monitoring: IC-9700 with minimalistic antenna

2021-11-18

Complainment about the need of having an elevated location and large antennas to become QRV on 23 cm with an IC-9700 inspired me to compare my regular equipment of:

  • Flex-1500
  • TV 144 MHz
  • TV 1296 MHz
  • LNA 0.35 dB NF
  • 3 m EcoFlex 15
  • Ringfeed
  • 3 m dish on top of the mast

with my IC-9700, usually in use for 2 m and 70 cm and a minimalistic antenna:

  • IC-9700
  • 5 m RG213
  • Ringfeed for 1296 MHz, just on a metal step on the roof

The dish in the upper right and the ringfeed to be seen in the lower left on the metal step, both beaming south. As signal source the beacon HB9BBD/B on 1296.050 MHz has been chosen, 323 km away, on the Rigi Scheidegg in Switzerland, 1670 m above sea level. It is transmitting 10 w into an array of 3 dipoles beaming north.

As the whole air space between Mainz, JN49CV, and Rigi Scheidegg, JN47GA26, is visible, a lot of reflections on airplanes can be expected.

The signal of HB9BBD/B is very strong in Mainz, 40 dB over the noise usually. The gain of the dish is estimated to 28 dBD. The gain of a ringfeed may be 2 dBD and as it has just been layed down on a metal step on my roof, I assume the difference to be more than 30 db.

As expected, the signal could be received with the IC-9700 as well. It is deep in the noise, but increasing, when airplanes cross the path, audible most of the time.

Wide Graph of WSJT-X is a nice tool to display weakest signals and I very often use it to monitor distant beacons. I recommend it to anyone, who want to start beacon monitoring.

Deep in the noise is the signal at the ringfeed and the IC-9700 at about the same time as on the screenshot before. But it is always there and many reflections can be seen, increasing the signal level. Interesting is that different reflections dominate in the two screenshots. That is caused by the different beam widths of the antennas.

The conclusion is, that there is no point of not to try on 23 cm with an IC-9700 and a small antenna. In this example the difference of the receiving systems is assumed to be more than 30 dB. When using a low loss cable, a LNA and a 3 m yagi along with the IC-9700 the difference will be not more than 10 dB, resulting in 20 dB stronger signals.

Aircraft scatter relativizes the disadvantages of locations in valleys and urban areas.