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Old 02-05-2011, 16:01
pilgrim42
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Here on the Fylde coast I've got the full 8-day EPG for Channel M but no useable signal, although at about 22 miles NW of Winter Hill I'm surprised to get anything.
Mike.
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Old 02-05-2011, 16:15
Muzer
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You probably just picked up the data for the channel (name, etc.) and are receiving the EPG data from other muxes... That's my guess.
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Old 02-05-2011, 16:21
Greebo
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I can confirm by observation that Channel M's EPG data is also broadcast on BBCA, D3&4, SDN, ARQA and ARQB from Winter Hill.
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Old 02-05-2011, 16:37
pilgrim42
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I can confirm by observation that Channel M's EPG data is also broadcast on BBCA, D3&4, SDN, ARQA and ARQB from Winter Hill.
Thanks for that. So loads of us in the catchment area are going to get EPG and no prog? Or is the intention to broaden coverage?
Cheers, Mike.
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Old 02-05-2011, 16:41
Muzer
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Channel M's mux is broadcast on much lower power than the others, I believe to avoid interference with further-away transmitters.
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Old 02-05-2011, 16:47
Ray Cathode
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Not only on lower power but a narrow beam from Winter Hill towards Manchester. At present the aerial template is not "omni" but according to plane_spotter it will be. If the frequency remains on UHF57, then the beam is further restricted until The Wrekin changes its COM mux frequencies in September 2011.
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Old 02-05-2011, 17:00
Greebo
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Thanks for that. So loads of us in the catchment area are going to get EPG and no prog? Or is the intention to broaden coverage?
Cheers, Mike.
Yes, I guess every receiver in the region will be getting the EPG data - but most will not display it as the channel isn't in their listing. The Channel M data doesn't seem to broadcast so frequently on the other muxes compared to its own mux- which makes sense, and I would expect all muxes to prioritise their own EPG data.

On coverage, there is an ofcom document linked somewhere on here that shows the current cigar shaped beam pointing towards central Manchester being allowed to widen somewhat once The Wrekin gets off ch57 also. Anything more than that would be down to negotiation between Channel M/GMG, ofcom, and someone's bank manager to fund a better mux.

p.s. anyone outside Granadaland who can run dvbsnoop, can you try "dvbsnoop -nph 18 | grep Sidebottom" - if you come up with any entries for Frank Sidebottom's Testcard, you are also seeing Channel M EPG data.
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Old 02-05-2011, 19:29
Mike_1101
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Yes, I guess every receiver in the region will be getting the EPG data - but most will not display it as the channel isn't in their listing. The Channel M data doesn't seem to broadcast so frequently on the other muxes compared to its own mux- which makes sense, and I would expect all muxes to prioritise their own EPG data.

On coverage, there is an ofcom document linked somewhere on here that shows the current cigar shaped beam pointing towards central Manchester being allowed to widen somewhat once The Wrekin gets off ch57 also. Anything more than that would be down to negotiation between Channel M/GMG, ofcom, and someone's bank manager to fund a better mux.

p.s. anyone outside Granadaland who can run dvbsnoop, can you try "dvbsnoop -nph 18 | grep Sidebottom" - if you come up with any entries for Frank Sidebottom's Testcard, you are also seeing Channel M EPG data.
Here he is
http://www.youtube.com/watch?v=j3Vbr...eature=related
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Old 03-05-2011, 10:57
Greebo
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The streams are back on again (alerted by email @ 10:42):
PID found: 271 (0x010f) [SECTION: Program Map Table (PMT)]
PID found: 2308 (0x0904) [unknown]
PID found: 2323 (0x0913) [PS/PES: ITU-T Rec. H.262 | ISO/IEC 13818-2 or ISO/IEC 11172-2 video stream]
PID found: 2324 (0x0914) [PS/PES: ISO/IEC 13818-3 or ISO/IEC 11172-3 audio stream]
No change to QPSK, FEC.

Some quick bandwidth measurements:

PID 32: 1538 kbit/s (channel M video)
PID 2323: 3092 kbit/s (new channel video)
PID 8191: 401 kbit/s (stuffing)
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Old 03-05-2011, 11:12
Greebo
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LCN is 201, there is EPG data.
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Old 03-05-2011, 11:42
daniel2015
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LCN is 201, there is EPG data.
DMOL have just updated there multiplex list and added movies4men to the local transmitter table.
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Old 03-05-2011, 13:44
pilgrim42
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Full EPG data for Movies4men now showing, as well as Channel M.
Mike.
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Old 03-05-2011, 13:58
plane spotter
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Not only on lower power but a narrow beam from Winter Hill towards Manchester. At present the aerial template is not "omni" but according to plane_spotter it will be. If the frequency remains on UHF57, then the beam is further restricted until The Wrekin changes its COM mux frequencies in September 2011.
I donít think I said it would be omni ,or I didnít think I said that?


The restriction of the antenna pattern imposed by the planners
does limit the beam width severely using interference to the Wrekin as the reason.

The very tight restriction in the radiation pattern towards the north east has no merit whatsoever and if relaxed would provide coverage towards Oldham ,Rochdale etc .

Once the Wrekin has completed DSO except for one small issue with regards to Biddulph , coverage for ch m will be improved
considerably , especially if the ERP is increased as is required to overcome the severe building clutter in central Manchester.

I am hoping that ch m will become a commercial success and serve as a good model for other would be local TV broadcasters.

Government policy is encouraging this and Ofcom are very helpful ,it is just the planners are the main stumbling block
or they have been in the past.

What is needed here is an audit of the coverage planning done by Arthingy for others wishing to own and operate there own
TV transmitter and multiplex , to ensure the conflict of interest of the planners doesnít adversely restrict coverage of others
who then would be a multiplex operator and competitor..

This conflict of interest and restrictions to coverage in my opinion has been blatant in the past and needs to be stopped.
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Old 03-05-2011, 17:56
Ray Cathode
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I donít think I said it would be omni ,or I didnít think I said that?
I thought that an omni type antenna subject to templates was implied once multiple directions were being considered. I suppose more logs could be added though. If I was GMG I know which type I'd be pressing for.
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Old 03-05-2011, 18:40
Greebo
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I just went hunting for the ofcom doc that was previously quoted - it has changed URL, so I'll requote it - but this is *not* new info, it is from October 2008:

http://stakeholders.ofcom.org.uk/con.../notice524/im/ which then links to the actual pdf, currently at: http://stakeholders.ofcom.org.uk/bin...tice524/im.pdf

P24 and p27 of the pdf show the two predicted beam patterns.
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Old 03-05-2011, 19:33
plane spotter
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I just went hunting for the ofcom doc that was previously quoted - it has changed URL, so I'll requote it - but this is *not* new info, it is from October 2008:

http://stakeholders.ofcom.org.uk/con.../notice524/im/ which then links to the actual pdf, currently at: http://stakeholders.ofcom.org.uk/bin...tice524/im.pdf

P24 and p27 of the pdf show the two predicted beam patterns.
You will see from the maps and antenna patterns that the coverage is poor , yet there is no restriction up to 70 deg yet the antenna pattern fails to take advantage of this .
With regards to interference pre DSO I believe if the correct beam tilt was applied the signal level reaching viewers around the Wrekin could be within acceptable protection ratios.
This can easily calculated and actual measurements done to establish without any changes to the existing set up
.
However after Wrekin DSO I believe the coverage can be extended considerably beyond what is proposed by the planners .
In my opinion this is very important to maximise coverage to increase revenue and along with a increase in power allow the full capacity of the mux to be used for other local telly uses.

As I have said before 15 TV programs would be possible once the majority of TV and STB's are DVB-2 from ch m,s multiplex
serving several million viewers.
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Old 03-05-2011, 20:53
marria01
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Anybody else notice the service is showing as scrambled in the SDT? I've checked on the mux itself and on PSB1 and movies4men is showing as CA mode 1.

I've found a single STB in my collection that refuses to add the service as it believes it to be scrambled.
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Old 03-05-2011, 21:22
Greebo
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Indeed, so it is:
Service_id: 28674 (0x7002) [= --> refers to PMT program_number]
reserved_1: 63 (0x3f)
EIT_schedule_flag: 1 (0x01)
EIT_present_following_flag: 1 (0x01)
Running_status: 4 (0x04) [= running]
Free_CA_mode: 1 (0x01) [= streams [partially] CA controlled]
Descriptors_loop_length: 24 (0x0018)

DVB-DescriptorTag: 72 (0x48) [= service_descriptor]
descriptor_length: 22 (0x16)
service_type: 1 (0x01) [= digital television service]
service_provider_name_length: 9 (0x09)
service_provider_name: "Channel M" -- Charset: Latin alphabet
service_name_length: 10 (0x0a)
Service_name: "Movies4Men" -- Charset: Latin alphabet
Samsung 19" and 50" TVs - ok. Humax HD Fox-T2 - ok. Sony Freeview/DVD recorder - ok. Tesco/Dion el cheapo freeview box - interesting... finds the mux, finds channel M, ignores movies4men completely - how odd! Exact model is Dion STB2AW09.
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Old 03-05-2011, 21:39
plane spotter
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Anybody else notice the service is showing as scrambled in the SDT? I've checked on the mux itself and on PSB1 and movies4men is showing as CA mode 1.

I've found a single STB in my collection that refuses to add the service as it believes it to be scrambled.
I am confused a little.

You are saying it is a FTA broadcast and you have a STB that is listing it as a scrambelled broadcast?
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Old 03-05-2011, 21:51
Greebo
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It does look like the transmission is flagged as encrypted despite the fact that the streams clearly aren't. It is an edge case as to how the decoders deal with it- some (most?) are ignoring the flag.

The other channels showng Free_CA_mode: 1 on the Channel M mux PID 17 right now are:
Sky Sports 2
Sky Sports 1
Channel Zero
edit: removed CNN from list
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Old 03-05-2011, 22:08
marria01
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Indeed, so it is:
Are you seeing the same thing on the other muxes?
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Old 03-05-2011, 22:21
Greebo
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Are you seeing the same thing on the other muxes?
Yes, same odd Free_CA_mode setting is visible for movies4men on muxes BBCA and on SDN - I've not checked the rest.
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Old 03-05-2011, 22:25
marria01
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Yes, same odd Free_CA_mode setting is visible for movies4men on muxes BBCA and on SDN - I've not checked the rest.
So it appears not to be a local config issue.
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Old 03-05-2011, 22:40
Greebo
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So it appears not to be a local config issue.
I'm not sure what you mean by that.

It looks like there is a fair chunk of information exchanged between the muxes at the transmitter before broadcast - mux parameters, EPG, etc - and I'd guess that exchange is all fully automated, so there will be a standard automated feed from the local mux into the other muxes (and vice versa). So one config mistake in the local mux could be automatically reflected out on all the other muxes.
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Old 03-05-2011, 23:17
marria01
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I'm not sure what you mean by that.

It looks like there is a fair chunk of information exchanged between the muxes at the transmitter before broadcast - mux parameters, EPG, etc - and I'd guess that exchange is all fully automated, so there will be a standard automated feed from the local mux into the other muxes (and vice versa). So one config mistake in the local mux could be automatically reflected out on all the other muxes.
No, there's no exchange (not in the strictest sense), it's one way, all the SI is managed centrally by the Beeb (or Siemens to be exact), including the collection, storage and dissemination of schedule data from the various providers. They build all the tables. If the fault exists on only the Manchester mux, the fault is likely to be a local config issue in the multiplexer they use up there manipulating the data in the tables (instead of just flipping table_id's). If the fault is present on more than one mux, that points to a central config issue.

EDIT: To clarify, the mux operators are 'in control'. But the platform configurations (including any changes) are handled centrally by a single entity. Any change requests are done through them.
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