Our activity and the collaboration with Turin's Politechnic

In 2005 we had the fortune to meet Professor Chiesa of the Aerospace Department at Turin's Politechnic, who by chance lives in Bra.

Discussing with him, it materialise the opportunity to work on the PICPOT project with his team at Turin's Politechnic, as Radioamateur consultants.

The objective of PICPOT project was to allow students building a small satellite (13cm side) working on our UHF frequencies bands.

At that point in time, in addition to provide suggestions on how to set-up the ground station at Turin's Politechnic, we decided to buid a second one located in our club in Bra, to be used as back-up for the reception of this satellite and to allow operating ham satellites from our club station.

Therfore, we bought the following material:

During first tests we had some troubles with the control box G5400. Probably due to shortcircuits, the transformed burned-up. Consequently, we had to proceed to its replacement and in addition we mounted two MIL connectors on rotors side and DB9 connectors on the control box to avoid other problems. You can find information on these modifications at this link.

As far as the antennas, we decided to start with UHF and VHF and to think about higher freqeuncies later on. We bought a 16 elements crossed Yagi for UHF and a simple 9 elements for VHF mounted in horizontal polarisation (both from Tonna). Unfortunately, they turned out to be not the optimum solution. The ROS, even mounting the antennas as per manual and replacing several cables and connectors, was always very bad (2,5:1 in VHF and even worse in UHF). At the end, we modified the connections to the antenna in UHF and we got a good ROS (< 1,5:1) even if we are not sure that the polarization obtained is perfectly circular. If you are interested, you can see some pictures of the modification to the antenna here. In VHF the problem has not yet been solved. However, everything seems working and we have already some QSOs in our log.

To complete our antennas shack, we built a helix antenna for VHF (in the HW & SW page you can find the description how to build it) which is good to communicate with the International Space Station. The received signal is good as you can see in this video (3.7MB) but we have never had the opportunity to contacts them.

For higher frequencies we recovered an unused 3m diameter dish and we are setting-up an azimuth-elevation pointing system. The objective is to use it for 23cm, 12cm, 6cm and 3cm bands.

PicPoT and E-STAR

As written above, in the frame of PiCPoT project of Turin's Politechnic, we made available a ground station (receiving only) as back-up of that built at Politechnic. Unfortunately, due to forthcoming moving from old to new location, in the occasion of PiCPoT launch, our station was mounted temporarily in a field near Marco IW1DGG's house. This allowed us to be ready on the evenin of 24th of July 2006 to receive the first signal from PiCPoT, even if not from our final expected location.

Via SMS we were in contact with students in Baikonur (Russia) and via internet we were following the launch status, waiting for good news. Unfortunately, around midnight, we received the sad news: the launcher exploded toghether with PiCPoT and all 18 satellites. The disappointment was big, in particular considering the big preparation work.
However, we take this opportunity to receive other satellites to confirm the good operation of our system. In particular we received good signals from satellites CO55 and CO57 (morse signal received from CO55 - 8MB and CO57 - 800kB) and we decoded the telemetry (plot of the decoded morse signal).

Our collaboration with Turin's Politechnic and with Professor Chiesa, did not stopped with the failed launch of PiCPoT. Even if a further launch was not in the plan, thanks to the experience matured with PiCPot, Professor Chiesa and his team started the development of a new satellite, named E-St@r. The satellite has been designed using cube-sat standard envelope, so to allow us to easily find "a lift" on a launcher. The satellite has been then selected as one of those to find place on the maiden flight of the European VEGA launcher.

This time our collaboration with Politechnic was bigger. We designed and built the telemetry/telecommand board of the satellite (in practice a TNC KISS) and our ground station will be the primary one for the satellite. Since the satellite is much simpler than is predecessor, we used the standard radioamateur communication protocol AX.25 at a rate of 1200bps, to allow any OM receiving and decoding the signal from the satellite. We are still evaluating with Politechnic the possibility to organise a sort of special diploma for all OMs that succesfully receive signals from the satellite and forward us the received packets.

You can find additional information on the home-page maintained by students of Turin's Politechnic or from our dedicated home-page.


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