SSTV from VK3ASC/P on VK3/VE-208

Mark, VK3ASC activated summit VK3/VE-208 Jarvis Creek Plateau on PSK31 and SSTV Saturday afternoon 31 May 2014. On 30m he sent a picture of the summit a number of times on Slow Scan TV. The first attempt was using Scottie 1 mode which takes nearly 2 minutes for a 240 line picture of 320 pixels. I was using MMSSTV but the software did not recognise the start of the picture so I kicked it off manually and so only received the bottom part of the picture.

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Mark is using Wolphi’s DroidSSTV software on his Android smartphone. I suggested he switch to Scottie 2 which reduces the transmission time to just over a minute. At the same time, I was fiddling with the audio input level on my soundcard as the level was saturating. This could cause the failure to recognise the start of the picture due to audio distortion even though SSTV is really an FM mode so amplitude variations should play no part. This is what was received in Scottie 2 mode:

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The start of the picture was being recognised and the whole frame was received. There was quite a lot of sparkly noise in the frame so Mark suggested sending again. I further reduced the input level in case the audio was still saturating. There were quite a few static crashes but it seemed as though the picture could be improved. The final picture received was this:

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There was a lot less noise this time and it was much more recognisable. Mark attempted to raise the contrast in this picture by adjustments in the DroidSSTV app but it seemed to have no obvious effect. Certainly, a great first attempt at sending and receiving an SSTV image from a summit. Also check out Matt VK2DAG’s blog as he received the images too.

Thanks to Mark, VK3ASC!

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