Technical operations: the ITV network 

14 August 2020

In silhouette, two men wrangle with a large dish

Southern Independent Television engineers setting up a microwave link


ITV 1967 front cover

From ITV 1967, published by the Independent Television Authority in December 1966

THE PROGRAMMES WHICH THE VIEWER RECEIVES from his local ITA transmitter originate from many different sources and come over routes which vary from programme to programme. It is an operation which involves the programme companies, the Post Office (which provides the bulk of the cable and microwave circuits), and the ITA transmitters.

The Independent Television system is unique in the way in which so many sources are linked together: this whole complex operation is known as ‘networking’. The BBC tends to route most of its programmes through a central control in London; regional studios then opt to pass on to the transmitter either the programme from London or their own local output. The ITV network, on the other hand, is re-established after each programme break, usually with a different centre of origin and only going to London for programmes actually originating there. The organisation of this network has become increasingly sophisticated over the years and provides one of the sources of vitality in the Independent Television service.

Let us follow a typical sequence of programmes as seen on the screen at home and see how they are brought to viewers.

The programme journal may announce the following series of items for a particular Independent Television region:

  • 1.30 Journey of a Lifetime
  • 1.45 News
  • 1.50 World of Sport (see panel)

If the viewer switches on his set in advance of 1.30 he will find a tuning caption on the screen. The complete sequence of items on the transmission schedule will be:

Post Office Tower

  • 13.25.00 ITA Tuning Caption (slide)
  • 13.25.30 Caption with music (slide/tape)
  • 13.28.37 ITA announcement and slide (slide/tape)
  • 13.28.50 Company Identification (slide)
  • 13.29.00 Announcer, giving programme details
  • 13.29.30 Journey of a Lifetime (35 mm film)
  • End with Symbol (slide)
  • 13.45.00 ITN News (from network)
  • 13.50.45 Announcer in vision
  • 13.51.00 World of Sport (from network)
  • 14.15.00 Commercials (3 minutes)

The News will originate from ITN’s studios in Kingsway, London; from there it will be passed by cable to the switching centre under the new GPO Tower and thence by cables and microwave radio links be passed on to the complete network. The news will start exactly on time and each local company will switch over as the ITN opening caption appears. The symbol from the local studio will be used here to bridge the small gap between the end of Journey of a Lifetime and the ITN News.

At the end of the news item the network will be switched over to receive the output from Teddington studios for World of Sport, which in itself consists of a large number of contributions from outside broadcast units covering various sporting events. This switch over of the network is locally covered by the announcer, seen in vision, while the engineers are busy checking that the next incoming programme is correctly routed and properly set up in both sound and vision.


A map of the UK, with areas covered by ITA transmitters shaded

The ITV network in 1967


Also the local station will be made to run exactly in step with the next incoming programme, line-by-line and frame-by-frame, so that at the correct time the announcer can be faded out and World of Sport faded in.

The announcer and engineers can then relax for a few moments, just making sure that all goes well, until their next burst of activity, the running of the commercials. These are always sent out from the local studio and involve using film, slides, the announcer, or videotape.

The ITN Newsroom

The ITN newsroom at Kingsway, London

To warn the local studios of a break for commercials a little striped dot appears one minute before the break on the top corner of the screen (usually out of sight on the home receiver) and disappears again exactly five seconds before the break. This five seconds allows the local film scanner to be run up to speed, ready to take over from the network.

So it goes on all through the day, sometimes from London, sometimes from Manchester, Birmingham, Cardiff, or a remote O.B. unit. More dramatically the pictures might be coming from America via a satellite, received at Goonhillv, converted from American 525-line pictures to 405-line pictures by ITN and passed into the network. Always the announcer is ready to come on the screen to hold the fort during a delay or to explain a breakdown. When the number of switching operations and miles of network route are considered, it is perhaps surprising how seldom any mishaps occur.

The following illustrate some of the technical operations involved in running the ITV network.






A mobile television unit




You Say

1 response to this article

Alan Keeling 14 August 2020 at 4:00 pm

One thing I miss is the daily start-up with Tuning Signal, company logo then clock.

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