Just another ISS Bounce QSO

February 13th, 2014

Tonight I had a sked with Jan to try ISS Bounce once again. We agreed in trying SSB after getting in contact in CW. Jan appeared shortly after rise of the ISS and it was no problem to exchange reports and confirmation with strong signals. Then we switched to SSB and I could hear Jan clearly, but my tracking software refused to stay in SSB mode. So I have to fix this bug for our next test.

Later we tried to detect reflections from Iridium 4. We expected to see something about -19 dB, but nothing was to be seen in the waterfall diagram. Maybe that the choosen pass wasn´t too high in elevation and we will try again. When Jan was operating PI9CAM on February 2nd, faint traces of reflections on COSMOS 1823 could be detected by Hannes, OE5JFL, Dan, HB9Q and myself. As it is quite time-consuming, to find reasonable passes of satellites, I wrote a small Excel tool get an overview over satellites, passes and elevations. It can be found for free download here: Visibility

Macros have to be enabled in your Excel. Just enter the date, time, period and the locators of the two stations in the approriate cells, click “Calculate” in the “ADDINS/Satellite Overview” menu and the worksheet will be updated. Don´t forget to fill the TLE worksheet with the latest data of your choice.

Another strange constellation (Update)

February 6th, 2014

While performing my beacon check on December 16th, 2013 at 8:30 UTC, I stated that all beacons seemed to be at a normal level. Except, when looking for DB0FGB (JO50WB) with the dish heading 85°. There was a constant carrier of about 20 dB 15 kHz up, keying F1ZBK (JN38BP). Expecting a big signal, I turned the dish to France. But the beacon was only 15 dB with QSB, when beaming directly to it at 228°. Then I turned the dish back to 85° and noticed, that HB9EME (JN37KB) joined the party.

2013-12-16 09_30 F1ZBK HB9EME 85deg

DB0FGB, F1ZBK and HB9EME with dish heading 85°

The rain radar didn´t show anything unusual and the F5LEN Refractive index forecast for Europe promised only marginal tropo conditions for this area. Only DL7QYs Condition Index for south Germany has been on a level of 7 (1 = poor; 10 = extreme).

2013-12-16 09_00 F5LEN index

F5LEN Refractive Index

DB0FGB was a bit above normal at about 15 db with little QSB up and down. F1ZBK was constantly at 20 dB, when beaming 85° and around 15 dB with QSB heading 228° (direct). HB9EME was up to 20 dB in 85° and peaking 15 dB in fast QSB when beaming 198° (direct).

Green: Paths from Mainz to the beacons
Orange: Paths of the beacons to the area of the supposed reflection point

I checked HB9BBD, F5ZBS, F1ZBI and others, but couldn´t see any similar effects. The angle was very small. When turning the 3 m dish 5° left or right, the signals disappeared. These conditions lasted for about one hour.

Path DJ5AR to DB0FGB (by AirScout)

Topographic profile between DJ5AR and DB0FGB

The horizon in 85° is about 80 to 90 km off. A plausible explanation could be a strong troposheric duct between the beacons and a reflecting topographic formation.

Update:

In issue 2/14 the german magazine “Funkamateur” published an article by Matthias Hornsteiner, DG4MHM “Prognosekarten für troposphärische Überreichweiten” (Prediction maps for troposheric ducting). Matthias explains the basics of ducting and analyses the models, the well known refractive index maps of F5LEN and W. Hepburn are basing on.

So I had the intention, to ask him about a possibility for a reconstruction of the wheater constellation of that day. I have to thank him very much for his comprehensive answer.

As Matthias explained, the situation, shown on the map, was quite common for this, as he describes it, “anti-winter”. But it holds the possibility, that warm air might glide onto cold air at ground level. And indeed, when he reviewed the data of weather balloons launched at Stuttgart on that day, he found indications for a strong inversion in an estimated level of 400 to 600 m over south Germany. That matches!

In a distance of 200 km from here, the the topographic profile shows a formation, high enough to reach the level of this duct, as well as the mountains of the Fichtelgebirge do, where DB0FGB is located. The distances from Mainz to the area of the supposed reflection point is between 200 and 250 km. From F1ZBK and HB9EME it varies between 400 and 500 km. So the total path should have been between 600 and 750 km.

 

Operating a SDR like a classic radio

January 9th, 2014

For a couple of weeks now I am using a DJ Control to handle my SDR. It is much more comfortable compared to working just with mouse and keyboard. An user interface, written by Tobias, DH1TW makes it possible to combine the benefits of a software defined radio with the comfort of an analog transceiver by pressing buttons and turning knobs.

SDR with DJ Console

PowerSDR can be operated by a DJ Control

Most of the control elements of PowerSDR like command buttons or sliders can be mapped to knobs and buttons on the DJ Control by the user. Of course I use the big knobs for VFO A and B. The one in the upper left is used for the RIT. The sliders in the center are mapped to control the gain of the headphone and the speaker. MOX, TUNE, CW, SSB, VFO switching and others have been mapped to real buttons.

My FLEX-1500 is mainly used to operate transverters for 1296 and 2320 MHz. The Interface works well on all microwave configurations up to PowerSDRs limit of 99.0 GHz.

Visit DH1TWs website for more information.

Review: Activityweek Rhineland-Palatine 2014

January 8th, 2014

The battle is over. I had my last QSO with Patrick, DH2PA on 70 cm just before the contest closed after seven days. There was a big regional activity on VHF, UHF and SHF, much more than last year. Finally I logged 414 QSOs on the four bands I have been active, compared to 266 in 2013. It is remarkable that there were many locals with improvised equipment on 23 cm. Just one new square on 2320 MHz could be worked during the activityweek: IK3GHY in JN65DM via aircraft scatter. But collecting new squares is getting harder and harder, the more are already worked. The tropo conditions remained normal during the seven days, so there was less DX than last year. This time I found four partners for 4-band-QSOs: DL7QY, DL8YG, DF5AY and DB6NT.

The top five of the most worked stations in this contest:
1. DL7QY    24 QSOs on 4 bands (2 m, 70 cm, 23 cm, 13 cm)
2. DC8WPA   18 QSOs on 3 bands (2 m, 70 cm, 23 cm)
   DJ1FZ    18 QSOs on 3 bands (2 m, 70 cm, 23 cm)
   DK0RLP   18 QSOs on 3 bands (2 m, 70 cm, 23 cm)
   DK7UP    18 QSOs on 3 bands (2 m, 70 cm, 23 cm)

Thank you all for your support and your patience!
Statistics:
        total       District K      DL ex K    F,I,OK,OZ,SM   Squares
BAND    QSO Stn     QSO Stn DOK     QSO Stn     QSO Stn       total new
 144    183  94      99  43  26      82  48       3   3          15
 432    134  66      69  31  20      65  35       0   0          10
1296     79  37      36  14  12      34  16       9   7          16
2320     19  11       1   1   1      15   7       3   3          10   1

Aircraft Scatter – useful for short distances

January 3rd, 2014

Thursday night I tried a QSO on 23 cm with DG2PU in JO30PH, what´s a distance of only 80 km. Unfortunately Thomas is located down in a valley with Taunus and Hunsrueck mountains between us. His neighbor Marcel, DK7UP is closed by, but up on a hill. While it´s no problem to contact Marcel on 23 cm, Thomas signal was only 41, peaking 51 from time to time. Since beacons in similar distances often produce nice signals via aircraft scatter here, I suggested to try a QSO using airplanes to get reflections, but Frankfurt airport was already closed at that time that there was only very little air traffic. So we tried this evening. Our antennas were elevated by about than 10°, because the hot spot was in a distance of only 40 km (and a heigt of 10.000m). The second plane passed by in perfect manner and I could copy Thomas for about 10 to 15 seconds with 57, enough to complete a QSO. Due to the short distance the hot area around the center of the path is relatively small and reflections will not last too long.

2014-01-03 09_36_19-AirScout -DG2PU

Path between DG2PU and DJ5AR in AirScout

Strange Conditions

December 11th, 2013

It is funny to check the beacons tonight. Most remarkable are two constellations, shown below:

2013-12-11 21_59 DB0VC and DB0AAT

While looking for DB0AAT in JN67HU, DB0VC in JO54IF could be received too. When beaming to Kiel, DB0VC can be heard even on 2320 MHz. It is beacon #9 on 13 cm.

 

2013-12-11 22_23 DB0NCO beats DB0FKS

DB0NCO beats Frankenstein

From my QTH DB0NCO has the same bearing as DB0FKS. The location of DB0FKS, the  Frankenstein Castle, can be seen visually from here in a distance of 34 km. DB0NCO is 203 km away but tonight it is stronger than DB0FKS, when coming up in QSB.

Back from Italy!

October 27th, 2013

Last night we returned from Italy, where we spent some days after the Alpe Adria Meeting. It was nice to receive the award for the 2nd place in the Alpe Adria Contest 2013 on 23 cm, to meet the Hams there and to have interesting talks with them.

DSC_9866 Alpe Adria 2013

Dino, IV3FDO was very hospitable and took some time to show us certain interesting places. So we learned, that the most delicious prosciutto of the world is produced in San Daniele and not in Parma.