Portsdown 2020 H264 not working

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Nick
Posts: 121
Joined: Sat Oct 03, 2015 10:09 am

Portsdown 2020 H264 not working

Post by Nick » Sun Aug 21, 2022 1:57 pm

Just updated my Portsdown 2020 from (version Buster 202010180) which is very old.

Rather than update the existing card I built a new one (version 202207170) and swapped the SD cards.

Now I get no modulation when H264 is selected in menu 12 when using S2QPSK or DVB-S and when using source as TestCard and Format 4:3 (No signal on spectrum analyser).

Modulation OK when MPEG-2 is selected.

What am I missing here ?

G8GKQ
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Re: Portsdown 2020 H264 not working

Post by G8GKQ » Sun Aug 21, 2022 3:56 pm

Hi Nick

We need some more information here:
  • What SR and FEC?
  • What modulator are you using (Portsdown Filter/mod PCB, Lime SDR or DATV Express)
Dave

Nick
Posts: 121
Joined: Sat Oct 03, 2015 10:09 am

Re: Portsdown 2020 H264 not working

Post by Nick » Sun Aug 21, 2022 4:36 pm

Hi Dave,

SR 333 and FEC 2/3 with Lime DVB on 146.5MHz.

I'm sure this worked with the old version I had as I was checking outputs a few days ago on the spectrum analyser.

Maybe I have missed a setting somewhere.

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Nick.

G8GKQ
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Re: Portsdown 2020 H264 not working

Post by G8GKQ » Sun Aug 21, 2022 6:49 pm

Hi Nick

That should work. It could be that there was a problem (GitHub or internet outage) during the build.

Please try an update. From Menu 3, check for update and then force update.

Dave

Nick
Posts: 121
Joined: Sat Oct 03, 2015 10:09 am

Re: Portsdown 2020 H264 not working

Post by Nick » Sun Aug 21, 2022 9:44 pm

Hi Dave,

Did an update even though it was the correct version and it did not cure the problem.

Put my old version SD card in and H264 works OK. Left that card in for time being.

I think I had a similar problem some years ago. I use the Three mobile network for my internet and I think it may corrupt the build for some reason.

Decided to order a ready built card, and while I am at it, to also get one to update my Ryde receiver.

Hope I don't have a similar issue with my Winterhill build - that is if I can ever find a Pi4 and voltage regulators for it...

Nick.

Nick
Posts: 121
Joined: Sat Oct 03, 2015 10:09 am

Re: Portsdown 2020 H264 not working

Post by Nick » Wed Aug 24, 2022 9:34 pm

Hi Dave,

Received the ready built card today and as expected H264 works OK.

I did some looking back on the forum and can confirm that I had the same issue with H264 failing after an update back in 2019. If I recall correctly it was after I updated using the Three mobile network. I seem to recall that a new build worked OK when I used TalkTalk landline internet to rebuild the card.

Not used TalkTalk internet for some time now as it is so slow here (1Mbps on a good day) so will have to try and get it working again to see if it will cure the problem with updates.

Must be something with the mobile internet network, even though I do get reasonable speeds with it.

Will do as suggested with the faulty card.

Regards,

Nick.

G8GKQ
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Re: Portsdown 2020 H264 not working

Post by G8GKQ » Thu Aug 25, 2022 8:51 am

Hi Nick

Pleased that the new card works OK. Do not try to update it until we know what the problem was, as the update does rebuild the H264 software, so you might re-introduce the fault!

I'll do some diagnostics once I receive the faulty card.

Dave

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