Category Archives: Tropo

Wiolas last Farewell

June 8th, 2023

It seemed, last weeks openings, brought to us by high pressure area Wiola, had been coming to an end, but at least it was back again.

After finding a simple fault in my IC-9700 I was able to receive as usual and worked stations from Germany, the Netherlands, Denmark. I heard SM7DTT calling CQ and working some stations from UK, but he didn´t copy me. Around midnight it calmed down and PA2M on 70 cm was the last QSO.

The early morning started with Germany again and Sweden was there as well and could be worked even on 70 cm. ODX on 2 m was SM6LPF in JO78CK over 1555 km, on 70 cm SM6VTZ, JO58IJ, over 1412 km followed by SM6CEN, JO67AJ over 1409 km. But the fulminant final was brought to me by Kjeld, OZ1FF, with a QSO on 23 cm. It took a lot of patience, but at least we did it.
Thank you Kjeld!

As in the previous openings I kept an eye on 144.300 MHz, called there a couple of times in SSB, but no sign of live in analogous modes. So all QSOs were done in FT8.

NB: QSOs on 2 m in green, on 70 cm in blue and on 23 cm in red.

Tonight Brian, OZ7SKY, requested a FT8 sked for 70 cm in the ON4KST chat. I was pretty sure, the condx were completely gone here in the west of Ireland. But I am used to give even the crazy things a chance and as the computer is doing the job, I agreed and could decode hin at once. During the first twenty minutes we had no more, than an nice chat on KST and me telling him the level I received him. The deep QSB on his signal was between -20 and -06, when he got my report and another 15 minutes later the relief: My RRRs.

While I am writing this, my PC decodes signals of OZ2OE and OZ4VW at low levels on 70 cm. As some CQs on 2 m, after working two GMs, didn´t find any takers, I closed down the station now.

Never say no to a sked request

Tropospheric Ducting at EI8HH

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 a 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 2 m 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 in the past.

On May 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, JO73ce 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 antenna 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.

Nice Opening tonight

November 29th, 2020

As predicted in the Hepburn forecast, there happened an opening to the west tonight. No really breathtaking distances, but at least three new squares on 2 m (two of them I already worked on 23 cm 😉 ) IN86, IN87 and IN89.

On 23 cm I tried with Grant, G1SDX in IO80FL, first in FT8, but I could only copy him via aircraft scatter due to significant doppler, inhibiting decoding of his signals. He copied me via tropo up to -11 dB, but we had a difference in power of 13 dB (36 element yagi and 10 W vs. 3 m dish and 200 W). So we tried MSK144, where I could decode him via AS, but he had no decodes of me.

It´s a very interesting path, as half of it is over water. It should be an opportunity for combined sea ducting and aircraft scatter. I hope for a chance to try.

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 

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.

OZ7IGY and friends

December 22nd, 2017

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.


A digital evening on 23 cm

October 25th, 2017

There was nice activity in JT9F on 23 cm tonight. It seems this mode works fine with aircraft scatter. I first worked Conrad, PA5Y in JO21VO (255 km) and Sam, G4DDK in JO02VO (540 km) via Tropo. Then logged a QSO with Neil, G4BRK in IO91HP using mainly aircraft scatter. In another test I decoded Neil, G4DBN in IO93NR (756 km) by reflections on airplanes. PA0JME and ON5KTO were calling CQ, but not replying to my calls. Instead I worked John, G4BAO in JO02cg (619 km) in an (too) easy way.

Worked stations in green, the heard ones in blue.

Anyway, it was a promising and exiting evening!

Addendum October 27th, 2017

Yesterday I logged Rien, PA0JME, Wim, ON5KTO and John, G4ZTR, also in JT9F on 23 cm.

Chatting with John, G4BAO, last night, I learned, he recently initiated a “Digifest” on the microwave bands every Wednesday. This resulted in what happened two days ago. In my opinion it´s a very good idea to have such an activity evening beside the regular contests.

Windmill Scatter

August 30th, 2017

As the weather forecast promised heavy thunderstorms for today, I was looking out for scatter points on 13 cm. Pointing to eastern France, I found a heavily scattered signal of DB0UX in JN48FX in 204°.

But the sound was quite strange and rhythmic. When taking a look out of the window, I saw the dish pointing at two windmills in 1 km distance.

This kind of scatter is not very helpful, but a nice experience anyway.

Disappointing Morning / Amazing Evening

August 17th, 2017

The whole morning I monitored EA2TZ/B in IN93BF on 1296.854 MHz over a distance of 1072 km, peaking up to 30 dB. The vertical profiles of 0:00 UTC from Paris and Bordeux showed an inversion at 1000 m altitude. F6DKW from Paris was booming here, but nothing could be heard of beacons close to the path or in tests with F6CIS, IN94WL and F6AJW, IN93EK. The duct was just too high.

Tonight Paolo, IK7UXW, JN80XP, asked me in the KST chat, to give it another try. We had discussed the possibility of combined propagation with aircraft scatter and tropospheric ducting before.

The path is perfect, as there is one hop over the Alps and a plain track over the Adriatic Sea.

On Tuesday last week, while I was watching the other Paolo aboard the International Space Station via HAMTV on 13 cm, Paolo had initial QSOs in this propagation mode with Daniel, DL3IAE, in JN49DG on 23 and 13 cm. That was a great effort! So I was more than poised for a try.

Paolo has a 2 m dish and QRO, so he started calling me in CW. I heard “musical noise”, EMEers know, what I mean, with very strong bursts from time to time, lasting for some seconds. After a while we decided to try in JT65c. And from the start I could decode Paolo in most of the periods.

The better decodes always correlated with airplanes, crossing the path within a specific window soutwest of Munich defined by a path with a virtual end at the coast of the Adriatic Sea.

Most impressive was the crossing of an A380-800

At the end some bursts could be seen again (after 30 seconds)

The whole Test took almost an hour to complete, as my TX power is about 10 dB less than Paolos. It is evident that JT65 with 60 second periods is not very useful.

Paolos reference for ducting on the Adriatic Sea is IQ3ZB/B. Tonight it was at S9 + 30 dB. With good conditions it can be at S9 + 60 dB. So we agreed in continuing the tests in other  digital modes and in CW as well as on 13 cm.