No decode displayed

Discussion about this major DATV Project. See https://wiki.batc.org.uk/The_Portsdown_Transmitter
G8GKQ
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Re: No decode displayed

Post by G8GKQ » Sun Jan 17, 2021 10:52 am

Jabi

I will do some tests later today.

Please could you try a different USB lead?

Dave

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Re: No decode displayed

Post by G8GKQ » Sun Jan 17, 2021 1:13 pm

Jabi

I have tested the latest Portsdown 4 release (202101090) both as an upgrade from the previous release, and as a new build, and I cannot find anything wrong with the LongMynd receiver software when used with the MiniTiouner.

Please could you try it again with a different USB lead, and nothing else connected to USB on the Raspberry Pi. Then tell me excactly what message is on the screen when you say that there is no decode.

Dave, G8GKQ

Jabi
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Re: No decode displayed

Post by Jabi » Mon Jan 18, 2021 10:36 am

Hello:
Please send me your email for send one video with the trouble.
The trouble is that the software identify ok the video, but no decode, ok?
73,s de Jabi, ea2aru.

Jabi
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Re: No decode displayed

Post by Jabi » Mon Jan 18, 2021 10:37 am

The trouble is with Portsdown4, not with Longmyd.

g0mjw
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Re: No decode displayed

Post by g0mjw » Mon Jan 18, 2021 11:24 am

Jabi wrote:
Mon Jan 18, 2021 10:37 am
The trouble is with Portsdown4, not with Longmyd.
What exactly are you trying to decode?

g8lce
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Re: No decode displayed

Post by g8lce » Wed Jan 20, 2021 3:35 pm

Hi all,
I'll jump in with my experiences of this.
I have one Portsdown 4 that has been running for weeks and I had no trouble with. I have another new build. I have updated both to latest software. I have a new Minitiouner Express. One portsdown receives well and displays the video (decodes well ) the old one does not decode except for H264 333SR from the local Pluto and therefore a strong signal.
I have changed over the bits between the two Portsdowns, changed the SD card in the old Portsdown for a new built one, and use a short USB etc. The no decode seems to be something to do with either the Raspberry Pi and screen of the old one or it could possibly be the supply but I don't think it is as it is doing all the other things ( TX, Langstone etc.) I have tried it with minimal connections too.
This old one used to work well and I have tried it on the original Minitiouner V2 and no difference.
I cannot see any other difference between the two Portsdowns apart from the age of the Raspberry Pi.
One last thing is that it would only decode the signal from the new Portsdown (1249MHz 333SR FEC 1/2 S2QPSK H264 4:3 Testcard) on the OMX Player. The other two players showed the MER27 signal etc. but no decode. Other TX signals from the Pluto could be decoded with the OMX as well.

Martin G8LCE

g8lce
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Re: No decode displayed

Post by g8lce » Wed Jan 20, 2021 4:01 pm

Well I have found the place of the problem!! I changed the Raspberry Pi 4 for another one everything else the same. The Portsdown 4 now works well!!! So what has happened to the old Raspberry PI?
Is it some firmware change in the Pi or something that has died in it. It is only the decode that did not work.
It works as a Raspberry Pi with the full Buster system and HDMI output.

Martin G8LCE

g8lce
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Re: No decode displayed

Post by g8lce » Wed Jan 20, 2021 5:08 pm

I have just noticed that I had not reconnected the LAN to the replacement RPi 4 that works in the 'Old' Portsdown setup that did not decode.
I reconnected the LAN and did a reboot.
Now I have lost the decode on the OMX player! The other two ( VLC and ffmpeg VLC ) still work.
Was OMX player updated on reboot?

Martin G8LCE

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Re: No decode displayed

Post by G8GKQ » Thu Jan 21, 2021 4:34 pm

I am finding it very difficult to reply to the posts in this topic, as there does not seem to be enough information in any individual post to enable me to reproduce the fault. Some responses:
  • OMXPlayer has not been touched in any Portsdown update recently. It still works on the new build that I have made today.
  • Jabi EA2ARU and I have been talking directly and it appears that he is unable to get VLC player to run, even on a new card. I am at a loss to know why, although I suspect some sort of hardware fault/incompatibility.
  • It may be that something has changed in the operating system (outside my control) that affects older or newer hardware, but as I am unable to reproduce any fault at the moment, I'm a bit stuck.
I have just checked VLC and OMXPlayer against local (Portsdown) signals and other signals on QO-100 and all seems normal with the latest production build.

Dave, G8GKQ

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Re: No decode displayed

Post by G8GKQ » Thu Jan 21, 2021 7:14 pm

Martin

Could your OMXPlayer symptoms be something to do with the fact that OMXPlayer will only play a video stream when it has an audio track, and the Portsdown test card/contest numbers/desktop mode does not have an audio track?

Test with a camera and mic and I think that it will work (H264 only)

Dave

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