AMC6 12144 GBN Parameters

[SatelliteAV]

Could someone verify the paramers broadcast in the tables for GBN on satellite AMC6 freq. 12144? I do not have TS reader at home.

VPID 33
PCR ???
APID 34

I am not able to read the PCR from the Table with several receivers and am wondering if they are not defining the PCR again?

 

[qwert1515]

I am seeing the following with TSReader:

VPID: 33
APID: 34
PCR: 8190

 

[SatelliteAV]

I am seeing the following with TSReader:


VPID: 33
APID: 34
PCR: 8190

Thanks Qwert1515!

Do you see any data transmitted and associated with pid 8190? Or is it just a dummy pid?

 

[Mr Tony]

I've tried both 8190 and 33 and they both work for that channel

default shows 8190 on Coolsat 5000

 

[qwert1515]

8190 is defined in the PMT and has a data rate of 16 Kbps.
There is also a PID 8191 with a data rate of 660 Kbps and not defined anywhere.

 

[SatelliteAV]

I've tried both 8190 and 33 and they both work for that channel

default shows 8190 on Coolsat 5000

The GEOSATpro DSR200c also shows PCR 8190, but I was doubting that it is a valid pid. Normally the PCR is referenced to the VPID and a separate PID is not transmitted for AV synchronization.

 

[qwert1515]

The GEOSATpro DSR200c also shows PCR 8190, but I was doubting that it is a valid pid.

I quickly looked at TheList and I noticed that Ohio News Network, RTP International
and a few of the Color Bar channels also use 8190 as their PCRs.

 

[SatelliteAV]

I quickly looked at TheList and I noticed that Ohio News Network, RTP International
and a few of the Color Bar channels also use 8190 as their PCRs.

I have occassionally observed 8190 defined as a dummy pid.

I have been trying to solve a issue with the DSR100c/200c not displaying video on GBN. Trying to figure out table error and a work around can be frustrating! Thought I had it solved.... Back to the code tomorrow.....

 

[SatelliteAV]

I've tried both 8190 and 33 and they both work for that channel

default shows 8190 on Coolsat 5000

What receiver? If no PID is defined or a dummy like 1111 is entered for the PCR, does the receiver still display video?

 

[Mr Tony]

What receiver?

Coolsat 5000 & Pansat 1500

If no PID is defined or a dummy like 1111 is entered for the PCR, does the receiver still display video?

no. If you enter 1111 I get nothing
I remember a couple years ago that there was a channel (I want to say Pentagon when they had that "pirate" version on G10...pirate as in the Pentagon had no records of it) that the given PCR of 8190 would have audio be off by 2 seconds but if you set it to the same as the video PID the audio was real close to the video. Thats how I knew on this one to try both the video PID & 8190

 

[B.J.]

I've seen several channels that had 8190 PCRs, and there was actual content on those PIDs. On the other hand, there are some DVB players that seem to treat 8190 as a dummy PCR and seem to ignore the REAL PCR PID. I know I used to use a program called DVBAPPS, which, if you couldn't get a channel to play with the REAL PCR PID, you would enter 8190, and it would ignore PCR info and play the program. Perhaps any PID that didn't exist would have worked, I don't know.

This channel, however actually does have PCR info in the 8190 PID. I just recorded a few seconds of the 8190 PID, and ran it through a DVB packet analyzer, and it actually has PCR info in there. Ie the packets are ID'd as being PCR packets, and you can see the time stamps changing in time. So in this case they are real, and not dummy PCR PIDs.


EDIT: BTW, I used a separate packet analyzer instead of trusting what TSREADER said because TSREADER tends to go by what the PAT/PMT info says rather than seeing the actual PCR packets. Whereas by inputting just the 8190 PID into an analyzer it wasn't confused by the info in the PAT/PMT.

 

[SatelliteAV]

This channel, however actually does have PCR info in the 8190 PID. I just recorded a few seconds of the 8190 PID, and ran it through a DVB packet analyzer, and it actually has PCR info in there. Ie the packets are ID'd as being PCR packets, and you can see the time stamps changing in time. So in this case they are real, and not dummy PCR PIDs.


EDIT: BTW, I used a separate packet analyzer instead of trusting what TSREADER said because TSREADER tends to go by what the PAT/PMT info says rather than seeing the actual PCR packets. Whereas by inputting just the 8190 PID into an analyzer it wasn't confused by the info in the PAT/PMT.

Thank you BJ for this additional information and confirmation of the PCR data. Trying to figure out what makes this a problematic channel on several receivers.

 

[B.J.]

Thank you BJ for this additional information and confirmation of the PCR data. Trying to figure out what makes this a problematic channel on several receivers.

When I tuned this in yesterday, I first tried on my Genpix Skywalker, and it was FULL of ERRORs on TSREADER. I thought this was strange, because this channel has always been quite strong on all other receivers I've tried it on. In fact I couldn't use this signal for peaking the sat because it was always PEGGED. I haven't tuned it in for a couple years though, so I thought perhaps it got weaker. But I decided to try on my Twinhan 1020a, which is running off the same signal that the Genpix is. SOLID reception. Then I remembered that I had observed that my Genpix seems to have problems with some narrow low SR signals. The SR of this channel isn't real low, but it's getting down there.
Anyway, most of my receivers don't start having issues until down below 2000, but perhaps the problems you're seeing with some receivers is related to the low SR? Perhaps the frequency steps aren't capable of hitting the freq right on? Just a thought.

 

[SatelliteAV]

perhaps the problems you're seeing with some receivers is related to the low SR? Perhaps the frequency steps aren't capable of hitting the freq right on? Just a thought.

All receivers scan and lock the channel fine. Some play the audio fine, but do not display the video. A few other receivers display video occasionally, but not reliably.

So far it is an exercise in patience and without resolution....

 

[Mr Tony]

Yeah the Geosats seem to have issues with this TP

Either you'll get audio and no video or video & no audio

 

[SatelliteAV]

The GBN channel is an unique and problematic channel.... The GBN issue occurs on many sample receivers and not just the DSR100c/200c. 4 of 6 sample test receivers with varying chipsets and tuners have issues with lip sync on this channel.
Addressing an AV sync issue on the next generation MPEG2/4 receiver with the GBN channel as well.

I am trying to determine what encoding parameter is responsible and develop a fix in the code to ignore the issue. Have a ticket in with the DSR100c/200c chipset developer to determine if the use of PCR pid 8190 is the trigger for the decoding error.

 

[B.J.]

The GBN channel is an unique and problematic channel.... The GBN issue occurs on many sample receivers and not just the DSR100c/200c. 4 of 6 sample test receivers with varying chipsets and tuners have issues with lip sync on this channel.
Addressing an AV sync issue on the next generation MPEG2/4 receiver with the GBN channel as well.

I am trying to determine what encoding parameter is responsible and develop a fix in the code to ignore the issue. Have a ticket in with the DSR100c/200c chipset developer to determine if the use of PCR pid 8190 is the trigger for the decoding error.

I don't know if this will help at all, but when I ran the 8190 PID through the DVBSNOOP program yesterday, it generated a text file showing the content of the PCR info. I have NO idea of what this data is supposed to look like, since I don't have any DOCs regarding the data structure, but you can see the time stamp info being generated. I've shortened the file to show only 4 packets, and attached it below, just in case you can see anything that might cause your issues.


EDIT: On looking at the file again, and comparing it to the original binary file, I see that the bytes shown aren't the actual bytes in the binary file. I'm not sure where DVBSNOOP got those "stuffing bytes". So I'm trying to also attach the original file. In the original, I can see the time bytes referenced in the analysis, so I think it did the analysis OK, but I'm confused by the bytes listed in the output. Usually DVBSNOOP does a good job on these PIDs, but this one does seem to be confusing it a bit. Anyway, hope the .bin file gets attached .

 

[B.J.]

.... Anyway, hope the .bin file gets attached .

.bin file didn't seem to go through, so I'm trying a zipped version.

 

[Mr Tony]

4 of 6 sample test receivers with varying chipsets and tuners have issues with lip sync on this channel.

very true. I havent seen it synced yet. Tried the Coolsat 5000, Pansat 1500, Geosatpro and BEC 6600
all are out of sync between the audio and video