We have both.  To receive SSTV, the APRS PSAT2 satellite supports it full time
with an SSTV image once every 4 minutes full time 24/7/365.on 435.350 MHz.

In addition, users can also uplink their own images to the SSTV transponder
on 29.481 MHz.  See how on http://aprs.org/psat2.html

The transponder is also available for PSK31 users.   - Bob, WB4APR

On Mon, Jul 19, 2021 at 1:13 PM GMM via AMSAT-BB <amsat-bb@amsat.org> wrote:
> Best Project first:
> If you have multiple projects and limited resources, you need to choose the project that will be the most successful or Get the best bang for the buck.
> What are you goals for an Amateur-Radio project for ISS?
>  
> #1, Generate interest in Amateur radio capabilities.
> #2, Encourage Non-Amateur-radio people to possibly get-into the Amateur-Radio or SWL Hobby.
> #3, Get more people excited about the ISS and is open programs that can allow the average person to participate.
> #4, Provide the ISS crew with some entertaining and excitement about their projects.
> #5, Language universal projects work best.
>
> The APRS project has a low following and does not generate much excitement or newspaper coverage.
> SSTV does great and all 5 of the listed categories.
> Why is SSTV better the APRS?
> SSTV is a project that will cross over between two hobbies,  
> Short-wave-listening and Amateur radio.  Most Short-wave-listening and 
> Amateur operators are capable of receiving and decoding SSTV signals.
> With 10's of millions of SWL+AR stations receiving these signals month after 
> month, you will see a huge interest in the abilities of Amateur Radio on ISS.
>
> You must have heard the saying "A picture is worth a thousand words".
> When MarexMG was running the SSTV Program in Space Station Mir, out SSTV
>  images were showing up in magazines and newspapers around the world.
>
> When was the last time you saw a New paper or magazine story 
> [Non-ham] talking about APRS from ISS?  Never!
>
> The MarexMG SSTV project was a huge hit.  Schools around the world 
> were setting up receiving stations to receive the images.  I remember seeing 
> a new story showing how the Great-Lakes ices was changing week after week,
> based on images from Mir SSTV.
>
>  If we want to build up a large amount of support for existing and future
>  Amateur radio projects on ISS, then we need to put our best project front and center.
>
> I am not talking about turning on SSTV for 1 or two weekend per year.
> I am talking about turning it on for a FULL 6 consecutive months in a row 24 hours a day, 7-days a week.

> Image cycle duration:
> Let's keep is Simple and Safe.
> Recommended format:
> To provide the greatest access and reduce Heat stress on the radio, 
> I recommend using SSTV format Robot-36.
>
> The reason for the low-quality Robot-36, is because the transmitting time
> is only about 36 seconds for each image.  I know this is the lowest quality
> image format, but since it’s the shortest, we can keep the radio cooler.
>
> All transmitters run MUCH hotter in Zero Gravity!
> And if the ISS Air pressure is turned down from 14 psi to 10 psi [Usually 
> during space walks], the radio will also run hotter at 10 psi, than at 14 psi.
>
> Maximum number of ISS-transmitted images per hour.
> 1 image every 5 minutes or 20 per hour.  And depending on heatsink
> temperature and cooling fan status, we may need to reduce the 
> number of pictures per hour to keep the radio cool.
>
>
> My goal is to expand the presence of Amateur Radio on ISS and other 
> satellites and the best tools we have on ISS today is Slow Scan TV.
> Let's generate some worldwide excitement and make this hobby grow.
>
> Turn off APRS!
>
> Turn ON SSTV for a FULL 6 consecutive months in a row 24 hours a day, 7-days a week.
>
> And then start watch the publicly generated by Marex SPACE-CAM1
>
> by Miles, WF1F