Tag Archives: International Space Station

Equipment Test on the ISS

September 27th, 2017

Tonight ESA astronaut Paolo Nespoli, IZ0JPA, aboard the International Space Station tested the amateur radio equipment in the Columbus Module.

Signal quality was better than expected, as it was a pass with quite low culmination at 48° elevation only. He could be heard well on 145.8 MHz FM as well.

Groundtrack of the ISS

The following pass at 20:44 UTC was more convenient and culminated at 62° elevation in the north. But Paolo could only be seen in the very first seconds, before he switched HamTV to blank transmission.

NA1SS calling GB4YOTA

August 8th, 2017

Another ARISS contact with an YOTA event in England was scheduled. HAMTV should be operated by Paolo Nespoli, IZ0JPA. As some nice video sequences could be received on 13 cm, nothing was heard on the 2 m downlink on 145.800 MHz in FM.

Reception of Live Video from Space: Thomas Pesquet, FX0ISS

February 13th, 2017

Today another ARISS contact has been established between Thomas Pesquet, FX0ISS aboard the Intenational Space Station and Collège André Malraux, Chatelaillon-Plage, France. As expected, the onboard DATV transmitter (HamTV) was in operation.

Blank transmissions have been received earlier, but today I could receive the TV pictures for my very first time. There was a lot of fading, but I managed to record a couple of sequences.

As the pass went overhead, I lost the signal, when the ISS approached the zenith, because the rotor had to turn 180° and it is too slow to catch up the bird again (full length video here best quality from 2:50 to 4:50).

The frequency used was 2.395 GHz. The equipment installed for reception is a 3 m dish with linear polarisation, a Kuhne MKU LNC 23 converter and a TT S2-3200 DVB-S receiver card in my PC with Tutioune3200 DVB-S software by F6DZP.


ISS Bounce Tests with new WSJT-X

September 13th, 2015

Following Jan´s (PA3FXB) suggestion, we tried the new experimental WSJT-X software. The mode, we chose was JT9 H. Also we agreed in trying full doppler compensation to be used on my side. Everything worked fine, as can be seen in the screenshot below.

2015-09-13 08_15_51-WSJT-X v1.6.1-devel by K1JT


ISS Bounce in JTMS

September 5th, 2015

Back from our holidays Jan, PA3FXB, and I had another test via ISS Bounce on 23 cm today. As I located a bug in my Doppler correction software, causing unwanted steps, it could be fixed by finding a workaround for the malfunction in compilers NOW() routine, for returning the correct time in milliseconds. So the improved Doppler correction is working smoothly as can be seen and heard in the signals received.

2015-09-05 09-51-15 PA3FXB in JTMS

PA3FXB in JTMS received by DJ5AR via ISS Bounce. Center frequency was 1296.300 MHz.

094915  2.5 2270  3 36  248     DJ5AR PA3FXB
094915  6.5  520  2 26  276     PA3FXB DJ5AR
094915  9.7  360  1 26  310     PA3FXB DJ5AR
094945 12.8  180  1 26   64     PA3FXB R27 R27   DJ5AR
095115  3.1  300  2 26  268     DJ5AR PA3FXB R27 R27
095115  4.1  320  1 26  205     PA3FXB R27 R27   DJ5AR
095115  7.1  300  1 26  157     R27 R27   DJ5AR PA3FXB
095115  8.5  320  2 26  153     R27 R27   DJ5AR PA3FXB
095115 10.1 1560  8 36   65     PA3FXB R27 R27   DJ5AR
095115 11.7  300  5 26  138     R27 R27   DJ5AR PA3FXB
095115 12.3  820  7 26  111     R27   DJ5AR PA3FXB R27
095115 13.7  680  4 26   40     PA3FXB R27 R27   DJ5AR
095145  5.3  440  2 26  115     PA3FXB 73 73
095145  7.6  740  3 26  271     73 73 PA3FXB
095145  9.3 1440  3 36  283     73 PA3FXB 73
095145 12.0 1180  5 36  244     PA3FXB 73 73
095215 10.5 1120  3 36   56     WOW
095215 12.8 1520  3 36  190     WOW
095245  4.1  740  1 26 -116     SUPER
095315  2.1  420  1 26   -7     73
095445 16.0  140  2 26  252     DJ5AR PA3FXB
095615 14.7  140  4 26  231     73 73 PA3FXB          

We even had some kind of conversation at the end 😉

As further tests showed, the full doppler correction on my side is working very well now. This enables potential sked partners to work on a fixed frequency by just tracking the International Space Station with the antenna.

Sked requests are welcome:  dj5ar (at) darc.de

Modes, successfully being used so far: CW, SSB, ISCAT, JTMS

SM7FWZ finally worked via ISS Bounce

July 13th, 2015

While yesterdays try for an ISS Bounce QSO failed by Ronny, SM7FWZ, missing my rogers, we tried again this morning. As this orbit culminated near the zenith for me, I decided to catch up the ISS on the descending part of the pass.

2015-07-13 09_50_40-Satellite Window Finder by DJ5ARSo I could avoid the singularity in the azimuth angle and we heard us right from the beginning with strong signals. As Ronny couldn´t copy any rogers yesterday, we had plenty of them today, as well as 73s!

Ground Track of the ISS versus the direct path between SM7FWZ and DJ5AR

It is remarkable, that Ronnys signal was audible on backscatter off the ISS, even when my elevation became less than 2 degrees. The slantranges to the ISS were about 2100 km for me and 1700 km for Ronny: A total distance of 3800 km!

This is the result of many tests and discussion before. Ronny transmitted and received on 1296.300 MHz during the whole pass and automatic Doppler compensation was done on my side for both of us.

It is funny, that we had a Moon Bounce QSO a couple of days ago, just to compensate some frustrating tests. EME is sooo easy!

Thank you, Ronny, for this fast and efficient QSO and enjoy your very special day!




Welcome Ronny, SM7FWZ, to the ISS Bounce community!

July 12th, 2015

After many previous attempts Ronny, SM7FWZ and Jan, PA3FXB, managed to complete an ISS Bounce QSO on 23 cm today. The rigs used, were a 3 m mesh dish with 375 W on the dutch and a 4 m solid dish with 300 W on the swedish side.

Ground track of the ISS versus the direct path between SM7FWZ and PA3FXB

The window opened from 2015-07-13 08:07 to 08:17 UTC. While the antenna tracking was done automatically by both stations, only Jan could perform Doppler compensation. So they used a kind of mixed mode in tracking the frequencies.

25544 2015-07-12-08-07 SM7FW PA3FXB ISS(ZARYA) (25544) DopplerRonny transmitted on 1296.300 MHz and tried to catch Jans signal manually. So I monitored the frequency, Ronny should be heard on my side. It is nice to see in the video, how Jan appeared on the very left, getting closer and closer to the frequency, Ronny could be heard.

Congratulations to this success!

ISS Bounce News from Poland

June 14th, 2015

Michal, SQ5KTM, has been successful in receiving reflections of the french GRAVES radar from the International Space Station.

The radar system is used for space surveillance tasks, located in JN27SI and operating on 143.050 MHz. Karl, DK5EC, has written a very informative article about monitoring GRAVES.


Blank transmissions from HamTV aboard the ISS

May 5th, 2015

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.

2015-05-05 12_17_54-MAs can be seen, everything is working fine, so I am waiting for the pictures now.



ISS Bounce again: now in ISCAT

January 4th, 2015

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.

2015-01-04 12_14_58-

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.2015-01-04 ISCAT QSO