Switchover notes - multiplex names
The Broadcasting Act 1996 (c. 55) originally set up the law that allows digital television to be broadcast.
The regulator was the ITC (Independent Television Commission) allocated six multiplexes, as provided by the Act.
Original allocations
Multiplex 1
Multiplex 1 was allocated to the BBC. The BBC can provide whatever services on it that it deems necessary. The multiplex originally ran in 64QAM mode, delivering 24Mbps.Multiplex 2
Multiplex 2 was allocated as follows:Multiplex A
Multiplex A was allocated to S4C, the Welsh language broadcaster.Multiplex B, C and D
These were allocated to British Digital Broadcasting, later known as ONdigital and ITV Digital. These were to be used for "pay TV" services. These multiplex originally ran in 64QAM mode, delivering 24Mbps.Freeview allocations
After the failure on ITV Digital, their multiplexes were put up for auction.Multiplexes 1 and B
Multiplex B was then allocated to BBC Free To View Ltd (BBC FTV). The BBC switched multiplexes 1 and B to 16QAM mode, delivering 18Mbps each to provide more reliable coverage but with an extra 12Mbps.Multiplexes C and D
These were awarded to Crown Castle International (CCI), which was originally part of BBC Engineering that was "liberated" from the BBC by the 1996 Act. These multiplexes were also switched to 16QAM mode, with 18Mbps each.Ofcom frequency negotiations
New names
The Ofcom international frequency negotiations for the digital-only terrestrial television used new designations for the multiplexes. These were:- Multiplex 1 - PSB1 ("Public Service Broadcasting")
- Multiplex 2 - PSB2
- Multiplex A - COM4 ("Commercial")
- Multiplex B - PSB3
- Multiplex C - COM5
- Multiplex D - COM6
Post-switchover names
To distinguish the multiplexes in the switched-over regions from the original ones, Ofcom now uses these names:- Multiplex 1 - BBCA ("BBC A") - back in 64QAM
- Multiplex 2 - D3+4 ("Digital 3 and 4 Ltd")
- Multiplex A - SDN ("S4C Digital Networks")
- Multiplex B - BBCB ("BBC B") - - back in 64QAM
- Multiplex C - ARQA ("Arqiva A") - back in 64QAM
- Multiplex D - ARQB ("Arqiva B") - back in 64QAM
Arqiva bought Crown Castle International.
Freeview HD
Freeview HD will provide, from 2 December 2009, a new service on Multiplex BBCB. This will be in 256QAM mode.Help with Freeview, aerials?
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