Pictures from the Sky 

21 December 2022


From Television & Radio 1985, published by the Independent Broadcasting Authority in December 1984

Although the main thrust of the engineering activities of Independent Broadcasting continues to be directed at the extension and improvement of the services based on large networks of terrestrial transmitters, full account is being taken of the exciting possibilities now opening up of receiving in our homes additional television programmes directly from space satellites hovering in ‘geostationary orbit’ 22,300 miles above the equator.

British viewers have long become accustomed to benefiting from space satellites for bringing pictures of major news and sporting events ‘live’ from all parts of the ‘global village’. Such relays have been possible for some twenty years, using the enormous ‘ears’ in the form of British Telecom’s huge dish antennas at Goonhilly Downs in Cornwall or Madley near Hereford.

More recently satellites intended specifically for the distribution of television pictures within a continental area such as North America or Europe have come into widespread use for distributing the pictures from a central ‘up-link’ terminal to a large number of separate cable-TV networks or to conventional TV transmitting stations. This system, widely established in North America for almost a decade, is now being used in the UK for the relatively few cable networks already offering additional programmes to their subscribers – a practice that seems certain to grow with the growth of new multi-channel cable systems. In the USA some 40% of homes are served by cable in addition to off-air television, though it seems inevitable that it will be many years before multi-cable, offering perhaps the choice of up to 25 channels of television, will be available in more than about a quarter or even less of British homes. The capital costs of putting in the new cable systems and the difficulty of providing many channels of programmes sufficiently attractive to persuade viewers to spend perhaps another £150-£300 [£540-£1080 now, allowing for inflation – Ed] per year seem certain to slow down the growth of such cable systems in a country where so many viewers are already using VCR video machines to increase their choice of films and programmes of special interest.


Two giant satellite dishes

Goonhilly Downs in 2014. Courtesy of Airwolfhound on Flickr. CC-BY-SA 2.0


There is one particular form of new television technology that is rising above the horizon of time: direct reception on small dish aerials of less than 1-metre in diameter of transmissions from more powerful satellites beaming their signals downwards to ‘illuminate’ a whole country. This technology has become known as DBS – direct broadcasting from satellites.

Although DBS has been advocated by some engineers since 1965 or so, the system until very recently had not progressed beyond feasibility studies and the occasional experimental ‘bird’. Even now, in 1984-85, DBS is still for many a dream of the future.

Three programme channels engineered to high technical standards, based on the advanced C-MAC transmission system first developed and demonstrated by IBA engineers, could begin in 1987 or 1988 if the proposals outlined by the Home Secretary in May 1984 for a joint ITV/BBC/independent project come to fruition. Three years after the launching of this joint Unisat system, the IBA may be authorised to go ahead with its own plans for two future channels on a second DBS satellite system.

In contradiction to the inevitable gradual spread of extra-choice cable networks, a DBS system would immediately be potentially available in all parts of the UK for reception in the vast majority of homes, although some viewers may have to be served by communal aerials and small distribution systems. But to receive DBS off-air will require a special dish aerial and additional electronics and will almost certainly require monthly ‘subscription payments’ for the right to ‘decode’ the programmes which are likely to be sent in a specially ‘encrypted’ or scrambled form; and some 2 million subscribers may be needed for a three-channel DBS system to pay its way.

The C-MAC satellite technology is assured. Industry has said it can provide the receivers. The belief is high that DBS will come to the UK in this decade, even though the established terrestrial UHF transmitter networks will for many years remain as the living heart of British television.


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