Re: [amsat-bb] Trouble with MMSSTV
Hope you don't mind that I shared your email (below) on-list, but I think you gave me a clue as to what I'm doing wrong and I would like folks to see a good example if they need it.
Your screen shows the single peak at 1200, then essentially nothing until the picture info between 1500 and 2300 , then down to nothing again. I also noticed that the little green signal strength (?) bar just to the left of the FFT display is quite low. I think maybe I've just had the input level up too high. I've got signal in the FFT portion all the way from 1200 to past the 2300 and the green bar about 1/3 of the way up it's range. Would that be enough to throw off the sync?
I may be able to clean up the signal just by turning down the volume. All helpful comments and suggestions are still very welcome.
Steve AI9IN
----- Original Message ----- From: Greg D ([email protected]) Date: 10/07/20 13:54 To: Steve Kristoff ([email protected]) Subject: Re: [amsat-bb] Trouble with MMSSTV
Hi Steve,
The SSTV signals from the ISS yesterday were kind of garbled. Multiple stations reported this, so it's not your (or my) station's problem.
Take a look at a video of a (good) pass on Monday last that I did for our club:
https://www.youtube.com/watch?v=Z_SkJ8_mtA4
The FFT display should show the specific peaks in the signal around the line sync on the left, and a separate band for the actual picture to the right of it. If it looks like an amorphous blob, that was the interference we all heard. Hopefully they'll get it sorted out upstairs and we can grab a few more pictures today. Next pass in just under an hour here...
Greg KO6TH
Hi Steve,
Not a problem. I should have done a reply to all...
The volume was turned down because the video recording software was complaining about it being too high. Normally, the bar graph on the left is up about mid-scale. You certainly don't want it pegged.
The "amorphous blob" I was talking about was due to the interference we heard yesterday. Pass in progress right now... First image just finished as the pass started, and it sounded clean. Good luck!
Greg KO6TH
Steve Kristoff wrote:
Hope you don't mind that I shared your email (below) on-list, but I think you gave me a clue as to what I'm doing wrong and I would like folks to see a good example if they need it.
Your screen shows the single peak at 1200, then essentially nothing until the picture info between 1500 and 2300 , then down to nothing again. I also noticed that the little green signal strength (?) bar just to the left of the FFT display is quite low. I think maybe I've just had the input level up too high. I've got signal in the FFT portion all the way from 1200 to past the 2300 and the green bar about 1/3 of the way up it's range. Would that be enough to throw off the sync?
I may be able to clean up the signal just by turning down the volume. All helpful comments and suggestions are still very welcome.
Steve AI9IN
----- Original Message ----- From: Greg D ([email protected]) Date: 10/07/20 13:54 To: Steve Kristoff ([email protected]) Subject: Re: [amsat-bb] Trouble with MMSSTV
Hi Steve,
The SSTV signals from the ISS yesterday were kind of garbled. Multiple stations reported this, so it's not your (or my) station's problem.
Take a look at a video of a (good) pass on Monday last that I did for our club:
https://www.youtube.com/watch?v=Z_SkJ8_mtA4
The FFT display should show the specific peaks in the signal around the line sync on the left, and a separate band for the actual picture to the right of it. If it looks like an amorphous blob, that was the interference we all heard. Hopefully they'll get it sorted out upstairs and we can grab a few more pictures today. Next pass in just under an hour here...
Greg KO6TH
participants (2)
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Greg D -
Steve Kristoff