All posts by Mike Dimmick
Below are all of Mike Dimmick's postings, with the most recent are at the bottom of the page.
igb2100: If they work now they will work after they move. If you don't have them now they won't work then either. It's down to whether your TV implements MHEG-IC correctly (or at all), receiving the multiplexes that carry the small MHEG-IC programs, and on having the TV connected to the Internet.
The way this works is that the multiplex contains Service Information mapping the logical channel number to a Service ID. In turn that Service ID points to a data stream, and that data stream broadcasts the MHEG program. If the box or TV is recognized as implementing MHEG-IC, and is one that is supported by the provider (information about the device and the MHEG interpreter is available to the MHEG program), the program uses the MHEG-IC interface to redirect the TV to the Internet stream. If it doesn't, it uses the existing MHEG features to show the 'not supported' text and a logo. These features have been used for 10 years or more to generate placeholders (using very little bitrate) for channels that are currently off-air - e.g. 81 BBC Parliament during the Olympics, or 71 CBeebies from 7pm to 6am - or are simply data services like 105 Red Button.
Because they appear as regular channels, the Electronic Programme Guide can be filled-in using Service Information data.
Because of the way this works, if you can't get the multiplex(es) that carry the Service Information, you can't view the service. At the moment, the CONNECT services (113-115) are on SDN, 110-112 and 116 are on ArqB, and The Space is on BBC B. For transmitters yet to switch over, each service is on the pre-DSO version of that mux (A, D and B respectively). Also, you will have to rescan the TV to get them to appear at all, as with any other service.
YouView will also be offering 'pure' IPTV services in their programme guide, the information about which will be downloaded by the box over the Internet, with nothing transmitted over Freeview. It remains to be seen whether any of the channels carried on commercial multiplexes decide to make live streaming available to YouView boxes and have their channels added to the YouView EPG, and whether it's possible for them to replace the non-functioning broadcast slots - their channel numbers on full-Freeview transmitters - if the receiver is missing one or more of the multiplexes (e.g. if using a Freeview Lite, PSB-only transmitter).
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Nedbod: The BBC A and ArqA multiplexes will move from their current channels, C62 and C61 respectively, to C50 and C49, some time in April 2013 (current plan, no specific date given). D3&4 will remain on C59 so *could* be affected by interference from 4G transmissions.
Whether your TV reception will be affected will depend on where the 4G base stations are located compared to your line-of-sight to Winter Hill, and the exact frequencies that each one uses. A 30 MHz band has been allocated for downlink (transmissions from base station to phone), from 791 to 821 MHz, in probably 5 MHz chunks (values of 10, 15 and 20 MHz are also supported, with more bandwidth providing higher bitrates, but the higher bandwidths - hence fewer channels - would means fewer cells could be fit in before having to repeat). The risk is of introducing intermodulation through too-high signals overall, though it has also been found that receivers (set-top boxes and TVs) tend to suffer poorer sensitivity when there is a loud transmission in an adjacent channel.
If a filter is required, C59 will require a shallower roll-off than for C60, but it would still be relatively steep, many dBs of roll-off over only about 8 MHz. It's possible that some filters would cost more than some Freeview equipment, but only because the equipment is now down to under £20!
The plan is for the spectrum auction winners to provide a fund for any necessary filters, and if a practical filter is not possible for this customer, to fund an alternative means of reception. There are concerns that the fund, for which £180m has been suggested as the total sum, is not large enough.
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Bit academic at this stage as Ofcom have not awarded the Local Multiplex Licence for the services to run on.
Arqiva's timetable for getting the stations into service is August 2014 for Grimsby and September 2014 for Brighton. Information from http://www.arqiva.com/cor….pdf Schedule 11 (page 100 of the PDF).
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Mark A: The reason for converting BBC HD to BBC Two HD is to *save money*. They don't need to employ a separate set of channel controllers, nor need to employ separate playout and continuity announcers. It saves a fairly piffling amount of money, compared to the overall BBC budget, but it's enough for it to be worth doing.
BBC Two HD will initially be a single national service as BBC One HD currently is. Nations services, matching SD, will come later.
Expect to see more BBC Three programmes getting late-night repeats on BBC One, and more BBC Four programmes getting late-night or daytime repeats on BBC Two. Partly this makes up for the loss of the spots on BBC HD, but mostly it'll be due to reduced content spending (in real terms).
If you're looking for someone to blame, blame this Government for freezing the licence fee rather than allowing it to increase in line with inflation, and for loading a bunch of required spending on the BBC licence fee that was previously paid for from other government budgets.
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Bernadette: The Wharfedale WDTR160 appears to be a rebranded Tvonics box, if the help guide at https://ukfree.tv/retu….pdf is to be believed. You could try calling the number on that page. However, the Tvonics website indicates that the company went into administration in June.
There's a suggestion that Wharfedale-branded equipment was sold by Argos. Try contacting wherever you bought it. Or, try searching for manuals for any of the other equipment listed in that document, if you can't find the manual that came with it.
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JG, Kev: "SI Data" stands for "Service Information" data. This is a broad-ranging term for any information carried on the multiplex that describes how the streams of data packets make up the multiplex, the information about what frequencies are used by transmitters transmitting this multiplex, and the electronic programme guide, along with programme delivery control information (accurate recording).
You would have to contact DMOL (www.dmol.co.uk) about any changes that have been made to the format of the SI data. The most recent changes listed relate to Network Change Notification Descriptors, which advertise (to compatible boxes) the retunes required for DSO in Tyne Tees and Northern Ireland, and for the renumbering exercise that was expected to occur on 19 September.
DMOL do use the DTG Testing lab to verify that their changes work on the majority of equipment in the wild, but it's possible they don't have a 3View box.
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Ken Collyer: DMOL is DTT Multiplex Operators Limited. It is a joint venture between the four main multiplex operators, weighted according to their ownership: thus the BBC and Arqiva have 33% shares and D3&4 and SDN have 17.5% shares.
In turn, ITV plc owns SDN directly, while it has a 12/15ths share of a 50% share of D3&4.
DMOL is not considered a customer-facing organization. Channels can complain to DMOL, viewers cannot.
Part of the problem is that most Freeview boxes do not automatically pick up these changes. The DVB Service Information specification allows for it, but they do not implement it. Newer boxes, particularly Freeview HD equipment, does do the right thing automatically.
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Gary Burgham: These boxes are known to have faults relating to the Network Information Table, which often show up at switchover as the retune is required. See http://www.digitaluk.co.u…tnit for who to contact.
The change to the transmissions was first introduced in late 2009, but most boxes were not affected until they were retuned. Updates to some equipment were transmitted, but you would have had to have your box in standby overnight on the dates that the updates were transmitted - some viewers never put the box in standby, either leaving it fully powered up at all times, or unplugging overnight.
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bri: The BBC does not yet have the facilities to produce regional news in HD. They plan to introduce services for Scotland, Wales and Northern Ireland to cover the full range of national opt-outs. At the moment, when regional news is on BBC One, BBC One HD shows a holding caption telling you to switch to BBC One SD for regional news. I expect this will continue for England.
ITV have only licenced a few HD and +1 services, I think to reduce the costs of monitoring multiple services as well as the costs of broadcasting them all on satellite. The list of services licenced on cable and satellite is at Ofcom | Cable and Satellite TV Channels , which shows that the services for Yorkshire and Tyne Tees are combined for HD - that means you'll get Leeds news, since the West Yorkshire region is larger/more lucrative for local advertisers than East Yorkshire or Tyne Tees.
ITV1 HD on Freeview is licenced as a national service with regional opt-outs so we can't see exactly what services there are. I believe the Freeview services are the same as the satellite ones, though.
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Wednesday 25 July 2012 10:10PM
How the torch relay is broadcast: BBC News - How the Olympic torch relay is broadcast live .
It uses the 3G network.