HamTV Reception Reports

[nils]

Hi, great to see HAM-TV installed and transmitting again.

Reception report from today, 2025-07-31, 16:39 UTC pass, 44deg EL max, received in JO21ex, Delft, The Netherlands:
2m dish, helix feed, cavity filter, LNA 0.4dB NF/58dB gain, USRP B200, satdump for demod, start 16:39 UTC, end 16:50 UTC, peak SNR 16.3 dB, blank image, on AZ/EL rotator

7 minutes of video was received. Demod was working fine in satdump, signal was weaker/had some multipath during first half of the pass (I guess related to TX antenna geometry/obstruction of TX antenna at ISS). Signal was good and stable during the 2nd half of the pass. Spectrogram of the pass attached below to give an impression of the SNR throughout the pass (start/end @ -1.5deg EL angle).

Best regards, Nils

P.S. FYI satdump seems to lock around 2.3-3.0 dB SNR (for the current DVB-S 2MSym/s 1/2 FEC signal)

[G4IMO-TV]

Just for info:- It is possible to receive pictures using a cheap aliexpress MMDS BT-281 2.2 - 2.4Ghz downconverter. Downconverting to 557Mhz into the Minitiouner. Just remove the dipole, fit an N Socket, and connect directly to the feed. Even with a quoted NF of 2.5 dB I managed MER of 7.4 on a 1M dish.

Nick.

Screenshot (151).JPG (350.37 KiB) Viewed 703 times

[nils]

Reception reports from today, 2025-08-01, from JO21ex, Delft, The Netherlands (tracked all visible passes):

• 11:02 - 11:11 UTC, 13 deg EL max pass, max SNR 5.2 dB, ~30 sec of video decoded, blank image

• 12:37 - 12:48 UTC, 47 deg EL max pass, max SNR 17.8 dB, ~7 min of video decoded, blank image

• 14:14 - 14:24 UTC, 86 deg EL max pass, max SNR 23.1 dB, ~4 min 51 sec of video decoded, blank image

• 15:50 - 16:01 UTC, 57 deg EL max pass, max SNR 19.6 dB, ~7min 12 sec of video decoded, blank image

• 17:27 - 17:37 UTC, 17 deg EL max pass, max SNR 8.4 dB, ~1min 10 sec of video decoded, blank image

• 19:06 - 19:09 UTC, 1 deg EL max pass, no lock, no video decoded

Generally same observed as yesterday; on most passes the first half of the pass has a weaker signal, the 2nd half of the pass has a stronger and more stable signal. Can provide the spectrograms in case there is any interest.

HW/SW: 2m dish, helix feed, cavity filter, LNA 0.4dB NF/58dB gain, USRP B200, satdump for demod, on AZ/EL rotator

Side note: The SpaceX Crew-11 dragon capsule is scheduled to dock to the ISS tomorrow, Aug 2nd, not sure if the ISS attitude was normal today or possibly different due the arriving capsule.

Best regards, Nils

[IU2KAC]

Just for info:- It is possible to receive pictures using a cheap aliexpress MMDS BT-281 2.2 - 2.4Ghz downconverter. Downconverting to 557Mhz into the Minitiouner. Just remove the dipole, fit an N Socket, and connect directly to the feed. Even with a quoted NF of 2.5 dB I managed MER of 7.4 on a 1M dish.

Nick.

Screenshot (151).JPG

What type of rotor did you use?

[G4IMO-TV]

Dennard Heavy Duty Camera Pan and Tilt Head.

[IU2KAC]

Dennard Heavy Duty Camera Pan and Tilt Head.

Wooahh, well, that's brilliant!!
I'd never heard of this solution.
Do you have any photos to show?
Thanks so much.

[G4IMO-TV]

This is a photo of the equipment I used. The circular piece of cardboard in the center was there temporarily, to check how well it tracked the Sun.

bafkreifr2ioqwfqyzerzrggkwtuba6n5eozhw42zncw6pw4o2cvfyvir4e.jpg (208.71 KiB) Viewed 303 times

Good luck with your project.

Nick
G4IMO

[IU2KAC]

This is a photo of the equipment I used. The circular piece of cardboard in the center was there temporarily, to check how well it tracked the Sun.

bafkreifr2ioqwfqyzerzrggkwtuba6n5eozhw42zncw6pw4o2cvfyvir4e.jpg

Good luck with your project.

Nick
G4IMO

Well, I was thinking of a more detailed image, but from a distance it's not ideal.
Anyway, I saw you used a regular pole to install the panoramic head; they usually need to be mounted on a tripod.
How did you mount it on the pole?!
Sorry for the questions, but I wanted to know if your project is feasible for me.

[G4IMO-TV]

The PTZ camera mount is mounted on the pole using items from my junk box. It's held by 2 old aerial brackets and an Alluminium plate. Additionally for added strength there is a 10mm bolt through the pole to hold it all together. It doesn't look pretty but does the job.
If you have basic mechanical engineering skills and the resources, anything is possible.

Please use my QRZ.com email address if you require any further help and I will try to respond to your request.

Nick
G4IMO

IMG_1104 - Copy.JPG (533.98 KiB) Viewed 178 times

[nils]

Reception reports from 2025-08-02 and 2025-08-03 from JO21ex Delft, The Netherlands:

2025-08-02 (note SpaceX Crew-11 docked before the first pass on that morning, maybe ISS orientation was different than usual and/or the TLE slightly off):

• 10:14 - 10:22 UTC, 8 deg EL max pass, no lock, no video decoded

• 11:48 - 11:59 UTC, 35 deg EL max pass, max SNR 14.5 dB, ~6 min 18 sec of video decoded, blank image

• 13:25 - 13:36 UTC, 81 deg EL max pass, max SNR 23.0 dB, ~5 min 30 sec of video decoded, blank image

• 15:02 - 15:12 UTC, 70 deg EL max pass, max SNR 21.4 dB, ~5 min 31 sec of video decoded, blank image

• 16:39 - 16:48 UTC, 24 deg EL max pass, max SNR 9.7 dB, ~3 min 7 sec of video decoded, blank image

• 18:16 - 18:22 UTC, 4 deg EL max pass, no lock, no video decoded

2025-08-03 (with SpaceX Crew-11 docked):

• 09:26 - 09:33 UTC, 4 deg EL max pass, max SNR N/A, ~1 sec of video decoded, blank image

• 11:00 - 11:10 UTC, 25 deg EL max pass, max SNR 11.5 dB, ~4 min 48 sec of video decoded, blank image

• 12:37 - 12:47 UTC, 71 deg EL max pass, max SNR 21.8 dB, ~5 min 31 sec of video decoded, blank image

• 14:13 - 14:24 UTC, 80 deg EL max pass, max SNR 22.5 dB, ~5 min 25 sec of video decoded, blank image

• 15:50 - 16:00 UTC, 34 deg EL max pass, max SNR 13.5 dB, ~5 min 18 sec of video decoded, blank image

• 17:27 - 17:35 UTC, 8 deg EL max pass, max SNR N/A, no video decoded, blank image

Generally same observed as before: the first half of the passes is weaker, the second half of the passes is stronger.
HW/SW: 2m dish, helix feed, cavity filter, LNA 0.4dB NF/58dB gain, USRP B200, satdump for demod, on AZ/EL rotator

Best regards, Nils