Analogue television in the United Kingdom

Before 2006, analogue transmissions were the most used method of receiving television in the United Kingdom. It is expected that terrestrial analogue transmission will cease by 2012 with a phased transition to digital terrestrial television (based on the DVB-T standard and generally known in the UK under the brand name "Freeview") occurring on a regional basis from 2008.

Major networks

*BBC One - Public network funded by a yearly mandatory licence fee.
*BBC Two - Public network funded by a yearly mandatory licence fee.
*ITV1 - Commercial network.
*Channel 4 - Commercial network (not available in Wales).
*S4C - Commercial network only available in Wales; 50% of programming in Welsh.
*Five - Commercial network.

Former systems

System A 405 lines
(discontinued)

Ch	Video (MHz)	Audio (MHz)
1	45.00	41.50
2	51.75	48.25
3	56.75	53.25
4	61.75	58.25
5	66.75	63.25
6	179.75	176.25
7	184.75	181.25
8	189.75	186.25
9	194.75	191.25
10	199.75	196.25
11	204.75	201.25
12	209.75	206.25
13	214.75	211.25
14	219.75	216.25

Television broadcasting began on an experimental basis by the BBC in London in 1936. Initially the service was operated using two competing systems,

The earliest television broadcasts used the 240-line Baird system and the 405-line Marconi-EMI system on alternate weeks. However, the Baird system proved too cumbersome and by early 1937 had been dropped and the Marconi-EMI system became the standard. This system was later codified by the ITU as System A.

Different broadcast stations across the country broadcast on different channels to avoid interference.

Broadcast was suspended during the war but resumed in 1946. The BBC was joined on this system in 1955 with the launch of commercial television in the form of the regional ITV network.

This was the sole system in existence until the preparations for the introduction of 625-line transmission in 1964.

It ceased broadcasting in 1985.

Current system

System I 625 lines

Ch	Video (MHz)	Audio (MHz)
21	471.25	477.25
22	479.25	485.25
23	487.25	493.25
24	495.25	501.25
25	503.25	509.25
26	511.25	517.25
27	519.25	525.25
28	527.25	533.25
29	535.25	541.25
30	543.25	549.25
31	551.25	557.25
32	559.25	565.25
33	567.25	573.25
34	575.25	581.25
35	583.25	589.25
36	591.25	597.25
37	599.25	605.25
38	607.25	613.25
39	615.25	621.25
40	623.25	629.25
41	631.25	637.25
42	639.25	645.25
43	647.25	653.25
44	655.25	661.25
45	663.25	669.25
46	671.25	677.25
47	679.25	685.25
48	687.25	693.25
49	695.25	701.25
50	703.25	709.25
51	711.25	717.25
52	719.25	725.25
53	727.25	733.25
54	735.25	741.25
55	743.25	749.25
56	751.25	757.25
57	759.25	765.25
58	767.25	773.25
59	775.25	781.25
60	783.25	789.25
61	791.25	797.25
62	799.25	805.25
63	807.25	813.25
64	815.25	821.25
65	823.25	829.25
66	831.25	837.25
67	839.25	845.25
68	847.25	853.25

When it was decided to introduce colour television, it was initially intended to add the American system NTSC to the British system A for a system that would have been known as NTSC-A. However the government instead decided to standardise on the European 625 line PAL system. Rather than broadcast on the existing VHF channels under system A, a new system was adopted known as System I. As such, the UK standard is PAL-I.

Broadcast on this system commenced in 1964 with the launch of BBC 2. It was later joined by BBC 1 and the ITV franchises, however these channels continued to broadcast on the VHF system A until 1985. BBC 2, Channel 4 and S4C (the latter two being introduced in 1982) only ever broadcast on UHF.

The British channel numbering scheme divided the spectrum into 49 channels numbered 21 through to 69. These channels were allocated to the broadcasters to allow for four channels nationwide, two BBC channels, the ITV network and a proposed second network for ITV to be called "ITV 2". This last network was never launched (though a channel called ITV2 was eventually launched as a digital channel in 1998), but the channels it was to be allocated were allocated to the commercial broadcasters Channel 4 and S4C instead. As such, when Channel 5 launched in 1997 a massive retuning exercise had to be undertaken at the broadcaster's expense. Even after this is was still not possible to transmit Channel 5 to the whole of the UK.

Due to the networks being nationwide, it is convention that television sets be tuned such that channel 1 is tuned to BBC One, 2 to BBC Two, 3 to the ITV network (later branded as ITV1), 4 to Channel 4 or S4C and 5 to Five regardless of what actual channel the station is broadcasting on.

In addition to the 5 national networks, a limited number of local stations are broadcast to various towns and cities under what is known as a Restricted Service Licence. These occupy channels unused by the other broadcasters that can be used without causing interference in other regions.

Digital Switch-over

The government is committed to switching terrestrial television broadcasting to completely digital by 2012. A company called Digital UK (formerly "switchco") has been set up to handle the change. The switch will be on a region by region basis using the ITV regions as a basis. The schedule was announced by Secretary of State for Culture, Media and Sport, Tessa Jowell on September 15 2005 at the Royal Television Society Cambridge Convention.{|Regional Order