Sota sstv?

Hello All,

Has anyone had experience/use of this application. Lot of activators use mobiles for PSK so just wondering if anyone has tried it with potential for SOTA?

http://www.wolphi.com/ham-radio-apps/droidsstv-2/

Mike

Not yet, but seriously considering it!

Tom M1EYP

In reply to M1EYP:

Oh good Tom, another string to the bow. There was a French SOTA activation last year or perhaps the year before running SSTV. I got their picture of the summit but they did not get my SSTV report. Another mode worth a shot I think.

Mike

In reply to G6TUH:
Mark VK3ASC has been sending SSTV from summits using DroidSSTV, most recently yesterday (UTC time) using Martin 2 mode. Results from his SSTV activations can be seen here: SSTV | VK2IO

Cheers,
Gerard - VK2IO

In reply to VK2IO:

Hello Gerard,

I was not aware of this so thanks for the info/link about Mark and his activities. 18 months ago I worked VK (not SOTA) with 15W on 20M which has been my best dx on sstv so far using DM780.

Thanks
Mike

Edit update: It does take me about 10 minutes to set up for SSTV but if alerted will certainly try 8)

In reply to G6TUH:

Maybe you can explain Mike but I don’t get SSTV done with computers. If we consider what SSTV was, an analog method of sending low res pictures. It has a certain bandwith x time requirements to send that lossy image. Fine, it used technology available to people at the time. If you built the monitor out of an old radar tube then even better. But it was a product of getting an image through and audio bandwidth and storing it.

As soon as you use a computer to encode and decode the image in the old analog SSTV ways then you’re being daft. Why send the signal in a lossy way when you have enough computing power to encode it and send it a loss less way. There’s only so much information you can send in an audio bandwith and however many seconds it takes. So use the computer to compress the image, add a whole host of FEC and send a decent quality image.

Andy
MM0FMF

In reply to MM0FMF:

Why send the signal in a lossy way when you have enough computing power to
encode it and send it a loss less way.

Probably for the same reason that computer-generated Baudot RTTY (45.5 baud) is still immensely popular, even though people could send any number of more efficient, error-corrected teletype modes in a much narrower bandwidth!

73,
Walt (G3NYY)

In reply to G3NYY:

RTTY is the same Walt. Do it on a computer and it’s tedious. Do with a real noisy, smelly clackater-clackater-ding-zzzzzzzzzrrrrrrrrrrpt-clunk teletype and it’s awesome. There is something about the rhythmic noise and motion of the mechanism and that fabulous smell of warm machine oil that means I can’t tear my eyes off a working teleprinter.

Andy
MM0FMF

In reply to MM0FMF:

Its fascinating to watch an expert knapping flint but I wouldn’t carve the Sunday roast with the result!

Whether you use MMSSTV, Hampal or Easypal or whatever, it isn’t the technology that is important, it is the image that you receive. I have spent many a happy evening exchanging my best photos for those of my friends on 144.5** FM. I neither know nor care how the program works!

73

Brian G8ADD

In reply to G8ADD:

If the image is important then why send it over a corruptible link when you could send it error corrected?

Or I have missed something?

Andy
MM0FMF

In reply to MM0FMF:
In an ideal world, you’d send the image using a digital mode with forward error correction. On a summit, you have to use what’s to hand and for Mark VK3ASC, that was an Android mobile phone. The only available software for sending an image uses analogue SSTV, so that’s what he did. Whatever the resulting image quality, an impression of the summit was transferred, and it was a thrill for both the activator and chasers - and that’s really the point.
Hopefully Easypal will be ported to a mobile platform, and then higher quality images can be transferred easily - but in the meantime we’re having fun already!

Cheers,
Gerard - VK2IO

In reply to G6TUH:
Hi Mike,

Yes I have this software on both my Android phone and tablet. I have only tried it locally (audio between phones) so far and not yet on a summit. You may find you get a response from some of the VK activators as I know they were about to try some SOTA-SSTV - the concept being to send a picture from the summit via SSTV.

Wolphi also makes an interface to go to an FT817 or similar that works well, to avoid any background noise you would get by simply putting the SSB rigs mic up against the phone for sending and putting the phone against the speaker for receiving. Please note if using an interface the 3.5mm socket on the phone/tablet has to be one for a headset (ie with microphone) not just a headphone. No problem on phones but most tablets DON’T have mic input and rely on the built in mic only.

73 Ed.

In reply to G8ADD:

Yes. I know the technical +/- of various modes, SSTV is just another fun option. I once had a ZX81 (yes one of those!) and I used to have a great time on 2FM exchanging tiny software progs and then running the programs. Absolute thrill if I managed to receive a prog that was not corrupted. Why do this? To see if we could :wink:

Mike

In reply to VK2IO:

“… it was a thrill for both the activator and chasers - and that’s really the point”

Spot on!
Mike

In reply to G6TUH:

I agree, sending an almost live image from the summit is entertaining, especially for chasers. But by analog SSTV using digital methods, it’s just so wrong.

Andy
MM0FMF

In reply to MM0FMF:

Anyone who follows me on Facebook or Twitter will see live images of activations from time to time. All images sent using digital techniques that do not use up HF bandwidth. Mind you, 3G is so rubbish on hilltops that I sometimes think sending postcards would be more effective.

73 Richard G3CWI

In reply to MM0FMF:
Hello Andy, yes perhaps but so many things are sometimes wrong.

I think it wrong to open a bottle of wine and not finish it off :wink:

Mike

In reply to G3CWI:

I have lots of Wolphi’s apps. They are really good, BUT - I’ve started taking a net-book to summits when doing PSK instead (small laptop).

I think, if you run the apps on a tablet then it would work out pretty darn good - but I only have an android phone and it gets mighty fiddly in the middle of ‘non-macro’ conversation.

For me SSTV has two sides to it. What a great way of sharing some awesome summit images that are ‘live’ - I can see the attraction to that. However, I’m the conversational type and SSTV, along with some of the weak, non-extensible modes like JT65a are just not for me.

On a side note - I’ve had some really interesting results using Olivia on 2m - but that’s a whole 'nother story :slight_smile:

Rob G7LAS

In reply to MM0FMF:

You are sounding like most of my friends, family and colleagues Andy. “Why use amateur radio at all when you can perfectly well talk to anyone in the world over Skype / phone / Facebook (etc etc etc)?”

I understand the distinct point you are making about the technology, but the answer is the same - “to see if I can”. OK, that will be with solutions available today as opposed to solutions available in 1981, but the spirit of experimentation remains nonetheless.

Tom M1EYP

In reply to M1EYP:

The bulk of amateur radio is conducted via legacy modes: CW, SSB, even AM and FM - they are all pre-war in origin, even pre WW1 in many cases! So for all but the most died-in-the-wool techies amateur radio is on a par with sailing, the equestrian arts, steam railway preservation and so on. In the arts, once photography became a stable technology there were questions about why one should bother having a portrait, still life or landscape painted when photography is more up-to-date and more accurate, and those questions were first asked over a hundred years ago, but people still stick pigments onto surfaces! For me, at least, it isn’t really about the technology, whether legacy or up-to-date, it’s about the DOING! One of the fascinating things about the DC bands for me (remembering that most of my time in ham radio was spent on V/UHF) is that you can experience and work with the interaction between the Sun and the Earth, watch the ionosphere changing diurnally, seasonally and in response to solar events. You don’t get that with a phone or computer! So, Andy, I can understand your puristic stance but don’t share it. I’m sure that we are all capable of doing silly things for the fun of it!

73

Brian G8ADD