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.

 

 

 

 

– April 24 – apart from amateur satellites, a lot of other scrap metal is flying over us, including meteorological satellites. NOAA satellites take photos continuously and it is relatively easy to receive from them. Using our antennas for tracking and FUNCube Pro + for reception, I recorded the signals broadcast by NOAA-15 on channel 137,620 MHz, when it flew over Poland today at 18:30. Kuba (my son) decoded the signals and generated photos using the article HERE (from chapter 5go). Here are the effects (left photo in visible light, on the right in infrared), and the SDRSharp window:

 

 

 

 

 

 

 

– May 1 – we celebrated the labor day with a set of satellite antennas and a rotor installed on the lawn near the HF5L club. The participants were: Wojtek SP5DPD, Mirek SP5GNI, Sławek SP5ICS, Marek SP5ISZ, Marek SP5IXS and Grzegorz SP5MI. Although only 7 QSOs could be made via satellites, the system tests should be considered successful. The next step is the final installation of the antenna system on the roof.

 

 

 

 

– June 13 2019 – it’s time for Oscar 100! See the new thread HERE.

– January 30/31 2020 – ISS again transmits SSTV pictures. The signal was strong, you could try on any antenna (145.800 MHz, FM, set Auto in the MMSSTV RX application – it switched itself to PD120). Here’s what I received on the not-movable vertical 4 elements Yagi antenna:

The coronavirus outbreak has frozen club activities, including the installation of antennas for low-orbitting satellites. The ISS is still transmitting, there are as many as 4 hams on the current shift. On December 2, 2020, they were transmitting SSTV images again – here’s what we managed to catch up:

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Until the possibility of installing a rotor antenna set at the HF5L club, it was installed in the home QRA SP5GNI in May 2021.

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The mast was attached to the chimney on the roof. A RAS azimuth/elevation rotor was mounted on it. The 2m antenna was Crossed Yagi 2×7 elements, the 70cm band uses 2 antennas 13-elements yagis. Antennas through the MX72N duplexer are connected to DBA270 RX LN preamplifier. This allowed the use of a relatively high-loss H155 coaxial cable, which in turn has the advantage of small diameter and ease of installation.

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The new UHF/VHF shack consists of FT991, GNI-r9 rotor controller (SP5GNI design) and a laptop with SatPC32 software installed. The first attempts were successful – in one pass of the RS-44 satellite 8 QSOs was done – from EA to UA0.

more tbd.

Miro SP5GNI

 

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