AMC 21

[B.J.]

One thing I noticed with the PBS muxes is that they have no NIT, or it's not transmitted constantly. I wanted Montana PBS on my Scientific Atlanta D9850, but it said there is no NIT in the mux, so I have to enter everything manually. On my Visionsat, I did a blind scan, and for channel names I'd get SVC_X Channel, where X is channel number within the mux. I'm not sure why.

I think Montana and the PBS transponders don't have an NIT possibly because they are sort of in an ATSC mode.
However I don't understand why the lack of an NIT would keep you from scanning in the channels. There are LOTS of channels up there that don't have NITs, in fact I'd say that MOST FTA transponders don't have an NIT. Usually when you can't scan in channels, it's because there isn't a PAT or PMTs. But I'm not familiar with the Scientific Atlanta, but that seems strange to me that it would require an NIT to scan in a channel.
Re the SVC_X thing, those PBS channels don't have an SDT either, and that's usually where the channel names would be, so all the receivers have is the channel number. I'm guessing the SVC comes from your receiver. On some receivers, if there is no SDT, you'll get things like TVX, or CHX when the SDT is missing.

 

[emuman100]

My Scientific Altanta has different tuning modes to try to extract the channels from the multiplex. Proper Powervu multiplexes require a NIT, I guess. I changed the tuning mode to FTA, and now it's in "degraded" mode, and will pull out the channels, but the channel name just shows "Name Unavailable". I have it tuned to the HD multiplex right now and it also contains no NIT. It seems to contain PSIP information, which the IRD cannot read. I have the ASI output connected to a QAM modulator and use a ATSC/QAM tuner to watch HD. The one PBS HD channel comes up with a channel name on my ATSC/QAM tuner, which tells me it contains PSIP information. That channel is probably for broadcasting directly over ATSC because it seems to be an ATSC multiplex.

Jonathan

 

[B.J.]

My Scientific Altanta has different tuning modes to try to extract the channels from the multiplex. Proper Powervu multiplexes require a NIT, I guess. I changed the tuning mode to FTA, and now it's in "degraded" mode, and will pull out the channels, but the channel name just shows "Name Unavailable". I have it tuned to the HD multiplex right now and it also contains no NIT. It seems to contain PSIP information, which the IRD cannot read. I have the ASI output connected to a QAM modulator and use a ATSC/QAM tuner to watch HD. The one PBS HD channel comes up with a channel name on my ATSC/QAM tuner, which tells me it contains PSIP information. That channel is probably for broadcasting directly over ATSC because it seems to be an ATSC multiplex.

Jonathan

Re containing PSIP info that the IRD isn't reading, I'm guessing that it just isn't there. Some of the PBS feeds have the PIDs that would normally have such info, but there isn't much meaningful in them.

I'm not sure when things changed, but I just noticed that the different PBS transponders now seem to be encoded differently. I *THINK* that they used to be all the same, in the simulated ATSC format, with very little info in many PIDs. However I just now looked at 12120, 12140, and 12180, with TSREADER, and they're different.

The 12180 transponder is a very simple DVB type transponder, with just PAT,PMTs, A/V streams. It's not trying to simulate ATSC, and it doesn't have any SDT, NIT, EITs, or anything else with textual info. No channel names at all in this mux, just the numbers.

The 12140 transponder seems to be in the simulated ATSC format. There is an EIT stream, but it doesn't have much except
*******************************
Starts: 12/19/2008 6:59:46 AM
Length: 03:00:00
EIT Source: EIT0
Name: PBS HD Program
Description: n/a
Descriptor: ATSC Caption Service Descriptor
ATSC Caption Service Descriptor:
Language: eng Format: Line 21 captions from Even field
Language: eng Format: Captions service 1
Descriptor: ATSC AC-3 audio Descriptor
ATSC AC3 Descriptor
*******************************
That's all, and the length data is even wrong.

For the channel 3, it has a TVCT PID, which has the following:
**********************************
Channel 3
Service Name: PBS1DTV
TSID: 1 (0x0001)
Channel Number: 80.3
Carrier Frequency: 0
Modulation Mode: ATSC (8 VSB)
Source ID: 3
Channel ETT: PBS HD Channel
Descriptor: ATSC Extended Channel Name Descriptor
Extended Channel Name: PBS1DTV 1
Descriptor: ATSC Service Location Descriptor
Service Location Descriptor:
PCR PID 49
Stream Type 0x02 (MPEG-2 Video) ESPID = 49 Language =
Stream Type 0x81 (AC-3 Audio) ESPID = 52 Language = eng
Stream Type 0x81 (AC-3 Audio) ESPID = 53 Language = spa
*************************************
TSREADER apparently picks up the channel names from this.


For some reason, as I was about to repeat the above for the 12120 transponder, my receivers seem to have completely lost all the horizontal channels for some reason, so I can't look at that now, but I *THINK* that before I lost it, that it was in the simulated ATSC mode. Weird that I lost the H signal from 2 different dishes. I'm hoping that I didn't run over the coax with my snowmobile.

But in any event, I don't think there is much textual info included on the PBS muxes, even when they include the streams.


EDIT: About a half hour after writing the above, the horizontal channels came back (I have no idea of what happened).
Anyway the 12120 transponder is in that simulated ATSC mode, and has even less info than the 12140 transponder. For example the EIT has:
******************
Channel 1
Service Name:
Provider Name:
Transport Stream ID: 1 (0x0001)

---------------------------------------------
Starts: 12/19/2008 9:59:47 AM
Length: 03:00:00
EIT Source: EIT0
Name:
Description: n/a
********************
which describes a channel that isn't even on the mux, and doesn't have any info anyway.

There is a CVCT section, but it has almost nothing, and what's there is incorrect.

So basically there isn't any accurate textual info on the mux that I can see.

 

[emuman100]

Awesome, thanks B.J. I don't have a PC DVB card or adapter so I couldn't see this info. I remember 80.3 in my local area. My local PBS would broadcast that exact feed, it would be PBS1DTV on ATSC channel 80.3. This was when they first started broadcasting digitally, and for a number of years they started broadcasting their own feed in HD. When they were broadcasting 80.3 they were getting it from a dish on their roof pointed to AMC 3. I'm very glad I pointed my 36' Fortec to AMC 21, because I enjoyed PBS1DTV and I enjoy Montana PBS, as well as their other feeds.

All this while I thought they'd label the DVB channels like SD03, SD04, etc in the 12180MHz multiplex. I'm guessing the CVCT has the actual ATSC channel names, such as PBS1DTV on the 12140MHz transponder. Thats why my ATSC/QAM tuners can read it, but the Scientific Atlanta receiver cannot. With the 12140MHZ transponder, PBS affiliates probably just pull the transport stream of PBS1DTV and feed it directly into the 8VSB modulator or whatever adds more PSIP data to it.

And maybe 12120MHz is the ATSC version of 12180MHz? Who knows.

Thanks though.

Jonathan

 

[emuman100]

Has anyone noticed the 12140MHz transponder has completely dropped? I can't pick up any signal from it. It seemed to have dropped sometime yesterday evening (1-1-09). The PBSNGIS site says something should have changed in terms of that transponder. Anyone else notice this?

Thanks.

Jonathan

 

[B.J.]

Has anyone noticed the 12140MHz transponder has completely dropped? I can't pick up any signal from it. It seemed to have dropped sometime yesterday evening (1-1-09). The PBSNGIS site says something should have changed in terms of that transponder. Anyone else notice this?

Thanks.

Jonathan

? No, it seems to be OK for me.
I was watching it yesterday up to about 10M EST, and it's still running right now, so I don't see any problem with it.
I also don't see any mention about it at the PBS site. Only transponder I remember any issue with was the 12120H, which they said was temporary. 12140 is supposed to be permanent I think. EDIT: It is highlighted in their file because I think those 2 channels have changed from being the PBS HD channel, and a feed channel, into what now seems to be the PBS-X, east and pacific feeds. Ie instead of having only HD programming, they now have their regular schedules there, some in HD, and some center formatted SD in the HD signal.

 

[emuman100]

I was going to try to re-align my dish, as something could have gone out of alignment. I always had trouble getting a strong signal on Montana PBS. My Maxpeak SAM Signal Meter would seem to find a vertical signal, but not a horizontal signal. I noticed Montana PBS would hardly lock, so maybe it is out of alignment.

I get 12180MHz with the upconverted HD channel and the rest in that multiplex. I never checked the SCPC feeds. I don't get 12140MHz at all. It could be bad alignment, but I'm not sure.

Jonathan

 

[B.J.]

I was going to try to re-align my dish, as something could have gone out of alignment. I always had trouble getting a strong signal on Montana PBS. My Maxpeak SAM Signal Meter would seem to find a vertical signal, but not a horizontal signal. I noticed Montana PBS would hardly lock, so maybe it is out of alignment.

I get 12180MHz with the upconverted HD channel and the rest in that multiplex. I never checked the SCPC feeds. I don't get 12140MHz at all. It could be bad alignment, but I'm not sure.

Jonathan

I HAD been having all sorts of problems with AMC21, from the first day it was up, mainly on the horizontal channels, but also was weak on that Montanna channel too. However for the past few weeks, that sat has been booming in for me with strong signals. I don't know if they improved their signal a bit after all the testing was done, or if my dish shifted a bit due to cold weather and wind (my AMC21 dish is just bolted to a big log wedged between 3 rocks, so it isn't too secure). But anyway, 75% (90% after the NFL season) of my satellite viewing is PBS, so I'm glad I'm finally getting that sat well, however I know that I'm going to need to move one of my dishes when the leaves come back on the trees in the spring, because all three of my dishes are looking through tree limbs for that sat.

 

[Mr Tony]

12140 booming in here on the Coolsat 8000
12180 just as strong

12104 (Montana) is funky as 12104 next door at 123 can cause some issues. If I bump the dish west I get really strong Montana PBS but the rest go in the crapper

 

[Mr Tony]

12140 booming in here on the Coolsat 8000
12180 just as strong

12104 (Montana) is funky as 12104 next door at 123 can cause some issues. If I bump the dish west I get really strong Montana PBS but the rest go in the crapper

 

[Mr Tony]

from the PBS website

ALL NEW HD CHANNELS ARE ACTIVE !!
The Public TV HD Channels are active on Transponders 22 through 24 of AMC-21. Standard Definition services will remain on Transponder 21 ONLY UNTIL FEBRUARY 10, 2009.

so the SD feeds will leave on 2/10/09i...these are the ones on 12120 H 30000

 

[Cadsulfide]

Does this mean HD or squat for PBS? Time to start watching EBAY for a HD box.

 

[Mr Tony]

sounds like it. The "other" channels (v-me, world etc) will stay SD but the main PBS is going HD

 

[eurosport]

from the PBS website

ALL NEW HD CHANNELS ARE ACTIVE !!
The Public TV HD Channels are active on Transponders 22 through 24 of AMC-21. Standard Definition services will remain on Transponder 21 ONLY UNTIL FEBRUARY 10, 2009.

so the SD feeds will leave on 2/10/09i...these are the ones on 12120 H 30000

Should I re-scan AMC21 since this was posted a few days after I finally got the 1.2 tuned to it?

 

[Mr Tony]

I would....just to make sure everything is there

 

[Cadsulfide]

sounds like it. The "other" channels (v-me, world etc) will stay SD but the main PBS is going HD

At least it's a good "pitch" for another reciever

 

[equant]

Anyone know if the Analog PBS on AMC-4 is going to disappear?

 

[Mr Tony]

yes it will be

 

[emuman100]

Turns out my Fortec Star 90cm need to be re-aligned. Seems like 12140MHz is weaker than 12120MHz and 12180MHz. Anyone else notice this? I notice the SCPCs are really weak too.

 

[DiscoLoveGrapes]

Yes - those singles as weak. I can fine-tune them in, but they are pretty low.