ISS SSTV Event: Dec 26-31

[royldean]

From ARISS release on AMSAT mailing list (sorry for the lousy formatting):

ARISS SSTV Event Scheduled for Dec26
December21, 2021— An ARISS Slow Scan TV (SSTV) event is scheduled from the International Space Station (ISS). The event is slated to begin on December 26 at 18:25 UTC for setup and operation and continue until December 31 ending at 17:05 UTC. Dates and times subject to change due to ISS operational adjustments. Images will be downlinked at 145.8 MHz +/- 3 KHz for Doppler shift and the expected SSTV mode of operation is PD 120. The main theme will be for this event will be lunar exploration. Radio enthusiasts participating in the event can post and view images on the ARISS SSTV Gallery at Welcome to the ARISS SSTV gallery. After your image is posted at the gallery, you can acquire a special award by linking to https://ariss.pzk.org.pl/sstv/and follow directions for submitting a digital copy of your received image.

 

[KC3ECJ]

Yay!

 

[eorange]

Remove the /and from your reward link please.

 

[jwt873]

Thanks for the info... Calendar marked.... (I did pretty well on their last SSTV run).

 

[jwt873]

Just bumping this thread as a reminder...

Pass predictions can be found here.. AMSAT - AMSAT Online Satellite Pass Predictions (I won't see the ISS until tomorrow ).

Note.. Enter your actual Lat/Long in the pass predictor. For some reason entering the Grid Square isn't all that accurate.

 

[Token]

Here is the first image of the sequence. First pass was an excellent high elevation pass for me in the Mojave Desert of California.

Second image of the same pass here:

However, the second pass was silent, nothing sent that I could tell. It was not a great pass, low El, but still it was above my horizon for 6+ minutes, and nothing was sent, so I suspect they either had issues or decided since it was such a marginal pass for everyone in NA and SA to just not TX.

T!

 

[vagrant]

It is doubtful they turn it off/deactivate due to a marginal continental pass. There are plenty of islands everywhere. When a scheduled TX does not happen it could be a malfunction, EVA, docking, or some other TX/RX necessity.

I heard a pass earlier today, but was busy and did not record it. There are four passes for us in California tomorrow starting just after 8:00AM. A really good one is just after 9:45AM that hits 56° at the apex ( at my location ). We should get two good images from that one.

 

[Token]

I heard a pass earlier today, but was busy and did not record it. There are four passes for us in California tomorrow starting just after 8:00AM. A really good one is just after 9:45AM that hits 56° at the apex ( at my location ). We should get two good images from that one.

I have 7 passes above my horizon tomorrow. The first one, about 0640 UTC is pretty marginal, with a max EL of only 3°, but the other 6 are pretty promising, with one (1440 UTC) at over 75°. The next day, the 28th, I have 6 passes (lowest EL 17°), the 29th I have 6 again (lowest EL 15°), the 30th I have 7 (but 2 are below 10° EL, so 5 good ones), and the 31st I have 7, but one of them is very low.

So between now and the end of the event I should have about 30 decent passes with 8 to 10 of them being very good.

T!

 

[jwt873]

Here is the first image of the sequence. First pass was an excellent high elevation pass for me in the Mojave Desert of California

Great images.. What antenna are you using?

 

[JamesWest]

passed over my QTH yesterday. nothing.

 

[jwt873]

Had two passes here in the wee hours of the morning. I left the radio and computer on all night to copy them while I slept. Unfortunately I never got any good images. They all have wide noise bars in them.

 

[eorange]

Not a great pic. I was using MultiPSK as an experiment; will try RX SSTV next time which is what I've used in the past.

 

[Scanning-NWA]

Why is SSTV mode PD120 used and not something more common like SSTV mode Scottie 1? I setup my Kenwood VC-H1 Visual Communicator to copy and sadly discovered that it don't have PD-120 capability the hard way when I had plenty of signal but never a picture! Does anyone know if VC-H1 firmware can be upgraded for PD-120?

 

[eorange]

This was a very low (18°) short pass, using a handheld beam indoors due to undesirable weather, so all things considered...

I was between transmissions. This time I used RXSSTV:

 

[vagrant]

Perhaps PD120 as it can handle a larger size image. PD120 is relatively new. I forget now what was previously used just a few years ago. With PD120 I can typically get two images in a good pass.

* As you now realize, and I did myself long ago, recording the audio is critical for decoding later. I still decode it on the fly using a phone and the Blackcat SSTV app, but having the recording is paramount.

Here is one from this morning around 1615 UTC. This was low on the horizon and it was raining, so just my regular dual band antenna above the roofline. I just saw the eorange pics. Maybe we can cut and paste to make a good one.

 

[Token]

Why is SSTV mode PD120 used and not something more common like SSTV mode Scottie 1? I setup my Kenwood VC-H1 Visual Communicator to copy and sadly discovered that it don't have PD-120 capability the hard way when I had plenty of signal but never a picture! Does anyone know if VC-H1 firmware can be upgraded for PD-120?

I am not sure, but my understanding is that PD120 is used because it is a 2 minute mode that allows 640x496 images. It is one of the higher resolution and shorter time period modes.

Scottie 1 would take almost the same time (110 seconds) to send a 320x256 image as PD120 does to send a 640x496 image (126 seconds). Naturally, they want higher res images if possible, so 640x496 is preferred over 320x256, and since the passes are so short (a long pass would be 12 minutes) they need a faster mode.

And they have to space out the images in time far enough apart that if an auto system triggers on the last lines of an image it has time to complete the frame before they start the next image. So if it takes a tad over 2 minutes for an image, and they allow 2.5 minutes between images, they only get 2 images out in a 10 minute pass.

Here is my capture of the image at 1615 UTC

T!

 

[Token]

Great images.. What antenna are you using?

Sorry, missed this. I am using the M2 Antennas 2MCP8A. I got it as part of the LEO pack, so I have the companion 70cm 436CP16.

I have it mounted on a Yaesu G-5500 EL over AZ rotor.

T!

 

[jwt873]

Sorry, missed this. I am using the M2 Antennas 2MCP8A. I got it as part of the LEO pack, so I have the companion 70cm 436CP16.

I have it mounted on a Yaesu G-5500 EL over AZ rotor.

THAT explains it.. Thanks

 

[Token]

THAT explains it.. Thanks

Yeah, it does feel a bit like cheating when using it for ISS SSTV.

T!

 

[vagrant]

Cheating is fun and even a handheld log periodic antenna will help. Anyways, here is why I record. The first image I posted was using the Blackcat SSTV app while it recorded the audio from the radio speaker. Here is the same pass, but using the recording, converting it to 11025 and mono using Audacity, rename it from wmv to mmv, then MMSSTV to open the new audio file directly and clean it up.

Anyways, the next pass in a few minutes will be better.