Posts Tagged ‘hamsat’

Made my first satellite QSO

As well as flying a high altitude balloon another of my aims this year was to finally make a satellite QSO. Pleased to say last night I finally achieved it!

Last month Abdel Mesbah M0NPT chairman of the Hucknall Rolls-Royce ARC came to South Kesteven ARS to give an informative talk on operating amateur radio satellites. Abdel was the first UK operator to receive the AMSAT-UK 73 on 73 award for making 73 confirmed contacts via the FUNCube satellite AO-73.  http://amsat-uk.org/2015/01/28/abdel-m0npt-73-on-73-award/

Abdel explained all the current active satellites, how to work through them and gave hints and described techniques for achieving success on this more challenging mode of operation.

Spurred on I opted to target the SO-50 satellite which until very recently this was the only satellite carrying a FM transponder. The satellite receives on 145.850 MHz and retransmits them on 436.800 MHz (+/- 10 kHz Doppler shift). Operation requires the use of CTCSS (PL) tones of 74.4 Hz which starts a 10 minute timer and then a 67 Hz tone used for the contact. More details of how to operate and a video are on the AMSAT-UK website

I initially tried using just a suitably programmed Baofeng UV-5R with a NA771 whip and could clearly hear the downlink on higher passes, I called a few times with no luck.

I hadn't monitored SO-50 much before and sadly it seems to suffer from very poor operating, with stations calling over contacts in progress, or stations continually calling CQ CQ seemingly oblivious to any reply and those that just keep calling "hola hola hola" for whatever bizarre reason! I would be lucky to get through the QRM with just the whip so I needed a better antenna.

Despite being extremely busy at the National Hamfest last weekend I did manage to get hold of a dual band Yagi that was reasonably lightweight for hand held use and capable of being easily dismantled for transporting. (The Moonraker YG27-35 Dual Band) it has a single feed point and two adjustable gamma match sliders and was easy to adjust using my analyser.

It has a single feed and I tried it with the Baofeng and reception of the downlink was excellent, again on a couple of passes I tried answering calls with no success.

Last night I decided to try again but with the FT-857D set at 10W output. I put it on a small workbench in the garden and powered it from my portable SLA battery. I ran split operation with the 2m Tx VFO set at 145.850MHz with 67Hz CTCSS, the 70cm Rx VFO set at 436.800Mhz I was able to adjusted it down in 5kHz steps during the pass. I got the wife to take a picture while I was operating.



As I started to hear the downlink I heard Abdel M0NPT calling and answered him, I was shocked when he came back and we exchanging details - that was it I had made my first QSO via an amateur radio satellite! Then amazingly other stations started calling me and I was able to also work DO2SYD.

I did manage to record it on a small dictaphone (did have a bit of a brain fade with my callsign at one point!)



I could get hooked on this...  There is also the new LilacSat-2 (CAS-3H) satellite with a FM transponder to try to work!So much to do, so little time...

Made my first satellite QSO

As well as flying a high altitude balloon another of my aims this year was to finally make a satellite QSO. Pleased to say last night I finally achieved it!

Last month Abdel Mesbah M0NPT chairman of the Hucknall Rolls-Royce ARC came to South Kesteven ARS to give an informative talk on operating amateur radio satellites. Abdel was the first UK operator to receive the AMSAT-UK 73 on 73 award for making 73 confirmed contacts via the FUNCube satellite AO-73.  http://amsat-uk.org/2015/01/28/abdel-m0npt-73-on-73-award/

Abdel explained all the current active satellites, how to work through them and gave hints and described techniques for achieving success on this more challenging mode of operation.

Spurred on I opted to target the SO-50 satellite which until very recently this was the only satellite carrying a FM transponder. The satellite receives on 145.850 MHz and retransmits them on 436.800 MHz (+/- 10 kHz Doppler shift). Operation requires the use of CTCSS (PL) tones of 74.4 Hz which starts a 10 minute timer and then a 67 Hz tone used for the contact. More details of how to operate and a video are on the AMSAT-UK website

I initially tried using just a suitably programmed Baofeng UV-5R with a NA771 whip and could clearly hear the downlink on higher passes, I called a few times with no luck.

I hadn't monitored SO-50 much before and sadly it seems to suffer from very poor operating, with stations calling over contacts in progress, or stations continually calling CQ CQ seemingly oblivious to any reply and those that just keep calling "hola hola hola" for whatever bizarre reason! I would be lucky to get through the QRM with just the whip so I needed a better antenna.

Despite being extremely busy at the National Hamfest last weekend I did manage to get hold of a dual band Yagi that was reasonably lightweight for hand held use and capable of being easily dismantled for transporting. (The Moonraker YG27-35 Dual Band) it has a single feed point and two adjustable gamma match sliders and was easy to adjust using my analyser.

It has a single feed and I tried it with the Baofeng and reception of the downlink was excellent, again on a couple of passes I tried answering calls with no success.

Last night I decided to try again but with the FT-857D set at 10W output. I put it on a small workbench in the garden and powered it from my portable SLA battery. I ran split operation with the 2m Tx VFO set at 145.850MHz with 67Hz CTCSS, the 70cm Rx VFO set at 436.800Mhz I was able to adjusted it down in 5kHz steps during the pass. I got the wife to take a picture while I was operating.



As I started to hear the downlink I heard Abdel M0NPT calling and answered him, I was shocked when he came back and we exchanging details - that was it I had made my first QSO via an amateur radio satellite! Then amazingly other stations started calling me and I was able to also work DO2SYD.

I did manage to record it on a small dictaphone (did have a bit of a brain fade with my callsign at one point!)



I could get hooked on this...  There is also the new LilacSat-2 (CAS-3H) satellite with a FM transponder to try to work!So much to do, so little time...

More SSTV from the ISS

Like many others around the globe I spent yesterday attempting to receive and decode the SSTV transmissions being broadcast from the International Space Station by the Russian Cosmonauts.

The SSTV activity had been due to last three days starting on Saturday but commencement was delayed by the NASA space walk.

Receiving the signal and decoding is relatively straightforward due to relatively high power used (around 25W) however getting a perfect image is a challenge and dependant on a number of factors.
  • The timing of the overhead pass. Due to the time taken to transmit the image and the three minute delay between each image it is possible to only be in reception range for the end of one image and the start of the next. 
  • The ISS is moving quickly and so the transmission suffers noticeable Doppler shift. FM is more immune to the effect but for optimal performance adjustment of the tuned frequency is required especially on high elevation passes (more information).
  • The ISS moves position, both in direction and elevation as it moves across the sky and will show up the peaks and troughs in a static antennas radiation pattern. This leads to bands of noise when the signal level falls. The use of a rotatable (and if possible tiltable) antenna (or even an handheld one) is the dirigour mode of operating satellites (and the ISS) for serious enthusiasts. 
  • Noise and local interference will also obviously affect the image.
Mission Control

I opted a two pronged approach, the Yaesu FT857D connected to my rotatable four element YAGI which is mounted horizontally for SSB and the old TRIO/KENWOOD TR9000 was connected to the X50 dual-band collinear mounted vertically.


I had two copies of the MMSSTV program running on separate laptops The TR9000 was left running largely unattended tuned to 145.800MHz, while the FT857D was tweaked to the optimum frequency while the YAGI antenna was rotated to the correct azimuth during the pass.

All adjustments were done manually and I use the Orbitron program for prediction and under the Rotor/Radio tab the frequency and azimuth are shown and updated during the pass (as can be seen in the screen show below)


I missed the first low elevation at 11:07UTC, but was able to monitor and decode images on all the remaining passes during the day, with some excellent results, the images show the full images decodes on both radio set ups as a comparison.

FT857D - Yagi

TR9000 - Collinear

FT857D - Yagi

TR9000 - Collinear

FT857D - Yagi

TR9000 - Collinear

FT857D - Yagi

TR9000 - Collinear

FT857D - Yagi

TR9000 - Collinear

I was especially pleased when one of my best images was featured on the Amsat-UK and the Southgate Amateur Radio News websites.

What was slightly worrying and it also happened during the last SSTV activities were some operators transmitting on the downlink frequency even during a pass, what sounded like someone keying up was responsible for the single noise line on another perfect image. I even received an unexpected SSTV image, complete with a call sign while the system was waiting for the next pass. I won't publish it here as everyone makes mistakes.

The experiments are continuing today but I am in work so will just leave an automated set up running on the collinear.

Judging by the messages on social media these SSTV activities seem to have captured the imagination of a lot of operators and several members of my local club South Kesteven Amateur Radio Society (SKARS) had their first go with some excellent results and are hooked! The images can seen on the SKARS Facebook page

Long may the activities continue, hopefully started to transmit some live images from space.

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