At the weekend, October 12, 2024, I received SSTV with the ISS in the country - to the directed antenna of Uda-Yagi from the second floor of the country house.

I want to share observations of the SSTV ISS of October 12, 2024. In this case, the antenna of 4-elements in vertical polarization was used, at an altitude of 4 meters above the ground (in the attic) with manual tracking from the west to the southeast. Receiver - Baofeng UV-5R connected to a 2-meter RG-213 cable using an adapter SMA-UHF. SSTV decoding software - Robot36 for Android operating system. Sound transmission this time without a cable, through the speaker of the station and a smartphone microphone.

Since the dacha is almost perfect conditions, I expected that taking pictures with the ISS would be much more successful than from the city, where buildings and wires interfere. And it turned out. The maximum signal level to the directed antenna 4 elements without an elevation increased, to about 58 by ear. The duration of good reception has also increased compared to work on an undirected antenna of the "rod" type on the roof of the car.

At the same time, about 10 seconds on a low elevation were poorly heard by the end of the transmission of the first picture - over Western Europe.

Then, after a pause, the ISS signal became strong. The 2nd picture was accepted almost completely, but with some distortions (lines displacement).

And the 3rd - almost completely, when leaving the station over the horizon. The reason for which only 2 images was recieved: a significant, several tens of seconds silent interval in the transmission program between pictures No. 1-2 and No. 2-3.

The transmission break was observed on the other day.

Regarding the reception, I can say the following: Antenna 4-elements Uda-Yagi for the ISS for 145.800 MHz - this is minimum, because A small hiss is heard (the radio station that the reception was conducted is Baofeng UV-5R, 50 km from the city there is no interference and there should be no sensitivity due to the overload of the receiver tract).

It is necessary to turn the antenna only 2 times:

• in one to three minutes from the appearance of the satellite in the west to the maximum altitude (apogee) in the south,
• three minutes after maximum altitude - when the satellite's altitude above the horizon decreases and the satellite leaves the sky in the southeast.

Why did some radio amateurs on the CQHam.ru forum notice a lack of reception in previous days—for example, on October 10th?

3 pictures and 2 transmission breaks (pauses) are transmitted over Europe:
1) The first picture - over Western Europe (intended for radio amateurs from M0, De, IK, F) in the UA1 of St. Petersburg is not accepted.
2) pause 120 seconds.
3) The second picture - over Russia for UA3. Transfer PD120 - 120 seconds. Total - 4 minutes or half of the orbit.
4) pause 120 seconds.
5) Third picture - for the Urals UA6 (PD120). Total 120 +120+ 120 +120+ 120 = 5 *120 = 600 seconds = 10 minutes.

Ten minutes is exactly the time during which the ISS station is visible at the latitude of St. Petersburg.

Conclusions and tips:

• The directed antenna of Yagi 4 elements is a minimum for receiving an ISS.
• To work with a space station from 1 degrees and taking two SSTV pictures, it is necessary so that the obstacles are absent from the horizon to the horizon. Otherwise, even outside the city, the forest interferes and the reception starts from 3 degrees above the horizon.
• Radio receiver in the station - the more sensitive, the better. Chip RDA 1846 in Baofeng has average quality, compared to the superheterodyne in the Yaesu VX-6R and a new SDR chip in Retevis RT-85.
• Continuous support of the ISS, judging by the signal, is not necessary, it is a loud 57-58 when directing the antenna to the south. You can rotate the short Yagi antenna in the horizontal plane twice per orbit.

P.S. According to CQham.ru, during pause in transmission on 145.800 there was a switchover of SSTV to the frequency 437.800 МГц. The frequency 437.800 MHz is Designated as the output frequency of the cross-band (pronounced "crossband") repeater of the International Space Station. Information about the use for the SSTV range of 70cm was on the website of the Fan Club of the ISS in last 2023. This year about the frequency of 437.8 MHz there was no information on the site Iss Fan Club, on another website on the SSTV diploma 2024 Same nor in press release.

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