Jump to content

Frequencies without PAT/PMT/SDT


Mattias Persson

Recommended Posts

I don't know if this is a bug or not but I canät find any information on Internet about this.

 

 

I have connected a Cinergy DVB-C card with CI interface to a local cable-tv company in sweden and they don’t send the PAT, PMT and SDT table on all frequencies only on the first one.

 

I have talked to them and they say that the standard is to only have those tables in the first frequency, they say it works on all TVs so it must be something wrong with the software in the computer and they have checked it with Macab that supply their equipment and sending the tables on the first frequency is standard.

 

Because of this I can only get the programs from the first frequency, the rest won’t tune in properly. How can I solve this problem? Is there a way to tune all channels from the NIT table and use the PAT/PMT/NIT/SDT tables from the first frequency? It seems that all TV's use the PAT/PMT etc from the first frequency since all TV's work in there cable network.

  • Like 2
Link to comment

..use the analyzer of transedit. Then you can check whether these tables are really missing on the other frequencies. Select a transponder and click on analyze. You can save the result as xml and attach it here in a zip file (deselect EIT data in the analyzer settings). (an analyzer screen shot will also do)

  • Like 2
Link to comment

I did check in the analyzer and the PAT/NIT/PMT tables are only available on the first frequency that the cable-company use. According to the guy I talked to who have set ut the cable network it is according to the standard to only have this signals on the first frequency and use those tables to set up all the other channels. It works on both a Samsung TV and an LG TV with built in DVB-C interface so it seems that it is OK for those divices to only recieve the PAT/PMT extc tables from the first frequency but DVBViewer will not tune in a channel if the PAT table is missing... I don't know what the standard says about his but obviously it works in all TV's.

  • Like 1
Link to comment
According to the guy I talked to who have set ut the cable network it is according to the standard to only have this signals on the first frequency

It is true for the NIT, but not for the PAT/PMT. From ISO/IEC 13818-1 about the PAT

 

Each Transport Stream shall contain one or more Transport Stream packets with PID value 0x0000. These Transport

Stream packets together shall contain a complete Program Association Table, providing a complete list of all programs

within the Transport Stream.

 

From ISO/IEC 13818-1 about the PMT

 

Each Transport Stream shall contain one or more Transport Stream packets with PID values which are labelled under the

program association table as Transport Stream packets containing TS program map sections. Each program listed in the

Program Association Table shall be described in a unique TS_program_map_section. Every program shall be fully

defined within the Transport Stream itself.

 

This guy simply has no clue of what he's doing. As a consequence you will have to read the PAT/PMT in the TransEdit Analyzer and to manually enter and add each channel with all parameters in the DVBViewer channellist editor. Some DVBViewer functions (like multiple audio stream recording) will not work, though.

  • Like 1
Link to comment

..if that is true, you can't use DVBViewer or any other dvb_standard_compliant_application (or manually add and edit each channel). But I'm still not convinced ;) Could you attach a xml file of one of those transponders?

Link to comment
As a consequence you will have to read the PAT/PMT in the TransEdit Analyzer and to manually enter and add each channel

Amendment: TransEdit should find all channels included in the PAT/PMT of the first transponder when scanning it, even if the video/audio streams are not present there. However, it will assign the parameters (frequency etc) of the first transponder to all channels, and it will be up to you to correct them.

  • Like 1
Link to comment

I will try to fix an XML as soon as possible (it's not my computer, it's a friends so I have to go to his place to get the XML). Isn't it strange that all TV models work fine in their network. That is the strongest argument from the cable network. The guy I talket to have asked Macab that supply the equipment about it and according to them It is correct set up but I don't believe so.

 

I will come back with an analyzer xml-file

  • Like 2
Link to comment

Amendment: TransEdit should find all channels included in the PAT/PMT of the first transponder when scanning it, even if the video/audio streams are not present there. However, it will assign the parameters (frequency etc) of the first transponder to all channels, and it will be up to you to correct them.

Then you'll need different PAT_sections/transponder -> 1 section/TID. It could also be the same PMT_PID for all services -> 1 section/SID (known principle from sat ;) )

  • Like 2
Link to comment
  • 3 weeks later...

..if that is true, you can't use DVBViewer or any other dvb_standard_compliant_application (or manually add and edit each channel). But I'm still not convinced ;) Could you attach a xml file of one of those transponders?

 

I have attached an XML file... What do you think about it? Will I be able to see the channels or is it not possible if the network dosn't change their signaling...

  • Like 1
Link to comment

The PAT in the XML file contains the services, PIDs etc of the 474000 KHz transponder (6 TV channels), nothing more. There is no according information for other transponders. With other words: Though the NIT lists all available transponders of the network (including reception parameters like frequency, symbolrate etc) and provides lists of the contained services (including the service IDs), the information in the XML file is not sufficient for receiving channels on other transponders, because the PIDs are unknown. The other transponders *must* provide a PAT and PMTs, otherwise no go.

 

Everything looks like normal SI tables of a standard DVB network. I can see no sign of a non-standard network.

 

What do you see in the Analyzer Window when you select one of the other transponders?

 

According to the guy I talked to who have set ut the cable network it is according to the standard to only have this signals on the first frequency and use those tables to set up all the other channels.

Most likely this only applies to the NIT (a usual practice in most DVB-C networks). Let TransEdit read the NIT by clicking the Update button. It will correct/add wrong/missing transponder data in your transponder list.

 

Looks like TV-Net is a normal DVB-C network, but you got wrong information or misinterpreted/misunderstood it, leading to wrong assumptions, and you got stuck on it. The normal procedure is:

 

- A receiver reads the NIT of a reference transponder, enabling to tune all other transponders and receive their transportstream (tuning doesn't require knowledge of the PAT/PMT content!)

 

- Tuning other transponders enables reading the PAT/PMT data which is present in their transportstream.

 

- The information in the PAT/PMT (particularly the PIDs) enables setting up the channels of the transponder.

 

With DVBViewer / TransEdit it's a bit more complicated, because they are no specialized DVB-C receivers.

  • Like 1
Link to comment
  • 3 years later...

I don't know if this is a bug or not but I canät find any information on Internet about this.

 

 

 

I have connected a Cinergy DVB-C card with CI interface to a local cable-tv company in sweden and they dont send the PAT, PMT and SDT table on all frequencies only on the first one.

 

I have talked to them and they say that the standard is to only have those tables in the first frequency, they say it works on all TVs so it must be something wrong with the software in the computer and they have checked it with Macab that supply their equipment and sending the tables on the first frequency is standard.

 

Because of this I can only get the programs from the first frequency, the rest wont tune in properly. How can I solve this problem? Is there a way to tune all channels from the NIT table and use the PAT/PMT/NIT/SDT tables from the first frequency? It seems that all TV's use the PAT/PMT etc from the first frequency since all TV's work in there cable network.

No solution yet?Same problem PAT/PMT only on one frequency. All dvb-c box work without this parameters. Something missing on DVBViewer I think.

  • Like 2
Link to comment

 

No solution yet?

 

You're responding to a very old topic. Last post was from @Griga and according to him the topic starter provided wrong or incomplete information.

 

Maybe you can be more specific about your problem.

  • Like 1
Link to comment
  • 3 weeks later...

Any solution to frequency without PAT PMD SDT parameters? My cable operator provider this parameters just in one frequency, so a can see only two channels.

  • Like 1
Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...