At present the HamTV transmitter, installed at the International Space Station is switched on. As the camera is not connected, only blank transmissions can be received, just to test the equipment.
As can be seen, everything is working fine, so I am waiting for the pictures now.
Jan, PA3FXB, and I were discussing the use of digimodes on ISS bounce for quite a while. Today we tried it with ISCAT-B and were successful with the first shot. As in the tests with Ronald, ON7FLY, on AS, we used 15 seconds periods.
From the moment on, traces could be seen in the waterfall diagram, decodes were possible.
When the ISS culmiated and the variation of the dopplershift was fastest, the frequency correction came to its limits. But while I am used to ISCAT in the meantime, I needed no decodes to hear, that Jan was transmitting RRRRs.
At least I decoded a 73 from him. The experiences with ISCAT in ISS bounce are very promising, although the 15 seconds periods are too long. So we have to discuss it and try with shorter ones.
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.
My presentation “Let´s Bounce” will be given on two more dates:
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
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
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.
At present the HAM TV transmitter aboard the International Space Station performs blank transmissons until August 6th, 2014. No camera is attatched, so only signal levels can me measured.
This was an opportunity for me to check out the FSTV-equipment, I set up during the last months. So my very first attempt last night was successful. I used the pass at 23:50 UTC on July 30th, 2014.
I am looking forward to see some pictures in near future.
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
After getting familiar in working us in CW via ISS Bounce, Jan, PA3FXB and I were looking for a new challenge. So we decided to try it in SSB. After some tests in the last days and finding a workaround for a bug in my PowerSDR, we completed a two way contact in SSB on a center frequency of 1296.300 MHz tonight. The doppler compensation worked well on both sides. Just minor corrections with the RIT were neccessary. The signals weren´t as strong as they were in the days before, but strong enough to copy even some 73s at the end. It seems to be the first SSB QSO via reflections on a spacecraft at all.
The audio recording starts with my recording of PA3FXB on one channel synchronized with Jans recording of my signal on the other channel.
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.
Once the news about our QSO were spread out over the internet, Jan and I had an overwhelming feedback from all over the world. Many sent just congratulations, but a number of hams supported us with additional information. Domenico, I8CVS did calculations using the radar equation. His results concerning the expected signal levels correlate very well with our recordings.
A lot of details about earlier attempts were reported by GW4DGU (ex G4DGU), VK3UM and VA7MM. Here a summary in brief:
Chris, G4DGU and John, G4ANB performed tests with Ben, SM6CKU in 1980 on 70 cm. Ben was able to copy a SSB burst of Chris reflected on a COSMOS 3 stage launcher.
Dough, VK3UM had several QSOs with Graham, ZL3AAD on 432 MHz in the 1990s by bouncing signals off the Russian space station MIR. It seems, they were the first to complete a QSO using a space craft as reflector!
In an AMSAT forum Miles, WF1F, reports about reflections of Joe´s, W2KQ, signal bounced off the MIR on 2 m while arranging school schedules with one of the cosmonauts in 1994.
We knew that Mark, VA7MM and Cor, VE7BBG (sk) had their first tests on 23 cm on May 16th, 2004, as Mark published on his website. He now told in an email about four(!) QSOs they had on May 23rd, May 25th, May 31st and June 5th, 2004. As far as we know now, this team was the first to complete a QSO via ISS bounce at all.
In end of 2007 a lot of activities happened on 144 MHz. Rob, PE1ITR tried with Mike, DK3WN, who received reflections. Peter SM2CEW nearly completed a QSO with Håkan, SM7WSJ and tried also with Petros, SV3AAF (more). Frank, PE1NFE and Rune, SM5CUI were able to copy the signals from Sweden as well. Bernd, DF2ZC completed on 2 m with Frank, DH7FB on December 9, 2007. They had three more QSOs in 2008.
Addendum May 2016:
I found a link to the website of Philippe, F6ETI, where he described the successful experiments with F6AGR to bounce reflections off the Russian MIR space station on 144 MHz in February 2001. As he told me, they performed just a one way test and had no QSO.
To be continued ……