Our satellite activity

After a series of meetings on VHF subjects in our HF5L club, we started to prepare for work through amateur satellites.

March 8, 2019 Piotr SQ5JUP made the first contact from home QTH via FOX-1D satellite (AO-92) on FM using the X300 antenna + duplexer MX-72A + IC-9100. As you can see, you can do without a directional antenna!

Mirek SP5GNI prepares and tests hardware and software at home. As of March 12:

– own construction controller for the azimuth/elevation RAS rotor (based on the new GNI-r5 controller). The controller uses the AlfaSpid protocol and is compatible with satellite tracking programs, such as Orbitron or SatPC32

– launching the rotor/controller/Orbitron set “on the table”

– installation of the SatPC32 program; it is much newer and better than Orbitron, it allows automatic compensation of the Doppler effect

– assembly of rotor and two-band 16 el. antenna  in the garden

– launching the set antena/rotor/controller/ T-991/SatPC32

– listening stations working via satellites (SSB, CW, FM)

– March 13 at 11:03 local time – Mirek makes first FM contacts via FOX-1D (AO-92) with PD4HDB and SQ2XE (big emotions, as always when the first time)

– March 17, 2019 – making of a 75-ohm cable with symmetrators and a line fitting two Yagis for 70 cm band

– assembling 2 antennas (made by SP5CIB) on the boom. Antennas are offset by 1/4 lambda from each other. This gives circular polarity. Such configuration results in a loss of 3 dB in relation to a single antenna, but thanks to this, polarization fades that can reach up to 20 dB are eliminated

– March 18 – test QSOs in a configuration with two FT991 radios. The SatPC32 program deals with rotor control and Doppler correction for both transceivers. The biggest achievement is 4 stations on FM with one SO-50 pass. It is one of the few satellites which has a downlink of 70 cm. Antennas have worked, but I thought that it would be better to hear. However, the preamplifier would not hurt. Definitely no quality for the 2 m band, 6 vertical elements are not enough – crossed yagi is a must!

– March 27 – receiving and the first successful decoding of frames from the PW-Sat2 satellite. This satellite is temporarily in low activity, charging the batteries. It sends a package somewhere like every minute

– March 28 – after mounting the antennas on the metal boom, the DBA270 preamplifier and the MX72N duplexer were installed on the mast. Thanks to this, it is possible to work on one FT991 in split on two bands with one coaxial cable. It works! We ordered a crossed yagi antenna for 2m.

– using our antenna system and FUNCube Pro + every now and then I can easily pick up, record and upload the received packets from PW-Sat2. I got QSL from the PW-Sat team!

– April 5 – receiving RTTY signals (70 cm) and SSTV (2 m) from a balloon released by the SP3KEH team in Poznań

– April 9 – installation and wiring of the Crossed Yagi 2×7 el (WiMo) antenna. The first tests were excellent, SWR = 1.0, the satellites are really heard good

– April 13 – work without the DBA270 preamplifier (broken down).  From April 11, ISS broadcasts SSTV images ( https://issfanclub.eu/2019/04/07/ariss-sstv-event-planned-with-special-award/ ). It is not easy to stick in time with the right trajectory and solve technical problems during a 10-minute flight. In addition, there were problems on the transmitting side – audio modulation very quiet. No luck to pick up any image in its entirety, the best three are shown below.

 

 

 

 

tbd.

 

Leave a Comment

Your email address will not be published. Required fields are marked *

5 × = 50