THE DEVELOPMENT OF RADIO: ‘Dit, Dit, Dit’ to DAB

Aug 022010

THE DEVELOPMENT OF RADIO: ‘Dit, Dit, Dit’ to DAB

On the 12th December 1901 a kite was flown above a hill in Newfoundland, and from it was hung an antenna wire about 200 metres long. This equipment was then able to receive a signal which was detected as the sound of three clicks – ‘dit, dit, dit’ – that were generated by the production of three sparks all the way across the Atlantic in Cornwall. This was the first long distance wireless telegraphy transmission and it demonstrated the potential of radio to the world. Transmissions were to remain encoded as Morse for years, but in the meantime, it meant that by connecting to the existing telegraph system, ships could communicate with land for the first time beyond the range of the eye or ear.

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The spark-gap transmitter had been invented in the 1880’s by Heinrich Hertz and the existence of radio waves had been predicted long before in 1864 through the use of James Clerk Maxwell’s mathematical modelling. Michael Faraday’s important work on electromagnetism had begun in the 1830’s and was later furthered by Tesla, so wireless transmissions had a relatively long time in the gestation period.
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Guglielmo Marconi is generally credited with bringing together all of the related technology to make the jump through the final hoop necessary for successful long range transmission, and it was he who was responsible for that kite being flown above Signal Hill in Newfoundland and the transmission of the letter ‘S’ in Morse Code in 1901.

In 1920, this system allowed Marconi to transmit less than one hour per week of short public broadcasts of speech and music to those interested enough to construct their own medium wave radio sets. The Government of the day allowed Marconi to step up his transmissions to a daily basis in 1922 and a news service was added to the programming which lasted for a half hour per day. The transmitter was in Essex and the audience numbers began to steadily expand as popularity increased. Because of this, it became apparent that there was an attractive business proposition for someone motivated enough to manufacture and sell receiving equipment to the eager public, but their interest had to be sustained by improving and expanding the services available to them. Marconi had the idea of creating a software consortium funded by the hardware industry where the main players in the market (including his own company, Western Electric, General Electric and others) came together and agreed to financially pump-prime a ‘British Broadcasting Company’, by bankrolling it for a period of two years. This would allow the creation of more broadcasting stations across the country, making a radio set an indispensable item in the home.

The Government reluctantly agreed to grant a public broadcast licence to the company in return for a sales tax on radios and a consumer licence fee and further stations were established (Manchester, London, Birmingham and Newcastle – all transmitting at 1.5 kilowatts) in addition to the Marconi company’s Essex establishment. The next two years saw a much bigger roll-out of new stations across the country as the 10 shilling consumer licence fee began to incrementally generate more funds. This growth in consumers and coverage was staggering by the standards of the day and, in fact, rather puts the uptake of DAB into perspective. From a standing start in mid-1922 to one year later in mid-1923, there were half a million licence payers. Bear in mind that this was a situation where there had been no licence to pay at all and a radio set was either a relative luxury, at a cost of over £5 for a powered set that could be heard by more than one person at a time through a speaker, or required the skills necessary for a home build. By 1925 the BBC had achieved almost complete coverage of the country, through the network of local Medium Wave transmitters, something that DAB has not yet managed in all the time it has been available.

The next major technical development to take place was in the use of the Long Wave band, which allowed national broadcasting to 1.5 million listeners from a single 25 kilowatt transmitter to be achieved in 1925. Having paralleled local and national transmissions meant that it was possible for some early exploration of the stereo concept to be carried out by beaming out the left channel nationally and the right one locally!

The Government, having been at first, almost obstructive to the development of public radio, finally saw the potential of the technology and decided to nationalise the BBC when it’s licence expired at the end of 1926, whereupon it became a Corporation. By the end of the 1920’s, the 1.5 kilowatt local transmitters were shut down and a 40 kilowatt regional service replaced them. The national service was being pushed out at 70 kilowatts. Regular Short Wave broadcasting, going out to overseas listeners began in 1932, however, the international radio traffic was not just one way as the BBC began to lose listeners from the south of England during certain times because Radio Normandie, a French commercial station began to air English language programmes from the International Broadcasting Company after it’s own French programmes finished. Later, Radio Luxembourg began with English language material with it’s huge 200kW equipment. Both of these companies were selling their advertising to UK companies and were using English celebrities to target the UK listeners and this tactic proved to be successful for them.

An alternative system was made available to the public and was analogous to cable TV in that subscribers paid a fee to have the standard BBC radio transmissions delivered to them through a wired delivery system. The service provider used the subscription fees to invest in the receivers and cabling infrastructure, while the customer had a loudspeaker with a simple on/off switch. They were popular in areas of marginal reception and BRS Ltd, one of the providers, did deals with local authorities in order to get the system installed into social housing schemes. BRS later became Rediffusion.

The war years caused a huge shake up in the field of radio broadcasting – not least with the halt to the foreign commercial programming. With the importance for morale and propaganda being recognised early on, bigger and bigger transmitters were being built and the public services were adapted so as to prevent their signals being used by bombers as direction beacons to help them find their way towards their targets. By the end of the war, the licence was being bought by over ten million at a cost of £1 and transmissions began to get back to something like what they had previously been.

Across the Atlantic, however, things had been moving in a slightly different direction as, before their entry into the war, the USA began to look at the Very High Frequency band coupled with the frequency modulation (FM) technique. This shift from amplitude modulation gave great benefits in noise rejection and signal stability, making radio a true high fidelity source.

The FM system was patented in the US by Edwin Armstrong in 1933 with five separate patents covering the various aspects of his system. His first regular broadcasts in 1935 were made from transmission hardware on loan from RCA, sited at the top of the Empire State Building.

British transmissions in FM did not begin until the end of 1955, and initially only in mono, with stereo available in London only, on a fortnightly basis from 1958. The Wrotham transmitter in Kent then went over to full time stereo in 1962, following the first regular stereo signals that had taken place at two stations in the US the year before.

The quality of these broadcasts was very good, but once again, the content was suffering from comparison to the competition. This was demonstrated best by Radio Luxembourg’s new 1.2 million watt medium wave transmitter which despite highly variable quality, with the signal constantly drifting in and out of tune, attracted growing numbers of listeners due to the programme material that was on offer.

This lead was then followed by the pirate stations which technically operated within the law, but angered the UK Government because of their avoidance of paying for a broadcasting licence by working just beyond the boundary of UK territorial water in the North Sea. Not only did this challenge the BBC’s near monopoly but it also created competition with Radio Luxembourg because the signal was usually more stable and was broadcast for far longer rather than just in the evening.

After four years the Government had had enough and this led to the introduction of the Marine & Broadcasting Offences Act which made such activity illegal in 1967. The other measure was to completely reorganise the service that the BBC provided. It was decided to introduce a new station aimed at the younger audience that the competition had captured – ‘Radio One’. What had previously been ‘The Light Programme’ became ‘Radio Two’, ‘The Third Programme’ was reborn as ‘Radio Three’ and ‘The Home Service’ became ‘Radio Four’.

The station started with less than 6 hours of scheduled programmes per day and didn’t become a 24 hour service for over ten years. All output was mono and on Medium Wave. The always progressively thinking record industry(!!) were afraid that the new station would play so much music that it would actually prevent people going out and buying records, so it lobbied for a limit to the hours that Radio One could broadcast recorded music. This led to a policy of the station hosting live sessions that were recorded and played back to an eager audience, who suffered the rest of the time because the remainder of the broadcasting day was made up by piping in the Radio Two schedule.

Also around 1967, there was a move back to the local radio stations of Marconi’s time, with an emphasis on community broadcasting. The public and press opinion seemed to be favouring locally based commercial stations, but the Government ran a two year trial of BBC stations based in eight locations around England. The broadcasts were in mono FM but from low powered transmitters, ranging from 2.5 Kw at Stoke on Trent and Durham all the way down to an unbelievably flea sized 30 watt output at Radio Sheffield. The experiment in community radio was deemed a success so that another twelve stations were created and their brief was expanded to increase their audiences by allowing them to mirror their FM broadcasts with Medium Wave transmitters if required.

The general election of 1970 saw a change in Government from the Labour Party, who had resisted all efforts from the commercial sector to get independent radio of the ground, to the Conservatives, who embraced the notion of an alternative service as described in a white paper that was published the next year. This resulted in an Act of Parliament which gave the Independent Television Authority the right to oversee radio broadcasts arranged as franchises under the new title of the Independent Broadcasting Authority. The business model demonstrated by Radio Luxembourg and the pirate stations had been so appealing to commercial enterprises because they operated on a system whereby records were played in exchange for cash from the highest bidder, and the music was punctuated by advertising that was also sold to the highest bidder. The music attracted the younger generation (who also went and bought the records) and that audience attracted the advertisers. So it came as rather a shock when it became clear that this was not the model favoured by the new Government, who had taken on board the lessons learnt by the community radio experiment. The prescription that was handed to the IBA by the Government required them to sell franchises for nineteen public service stations over a period of four years – the public service was to encompass the needs of the whole community rather than just the record buying teenagers. The requirement was to completely follow the lead taken by the BBC local stations, but to be funded by advertising. This extended not just to the content, but also to the technical standards of the broadcasts – if they were to earn the right to a broadcast licence, the quality of the output signal had to be up to snuff too!

The first two successful franchisees were LBC and Capital Radio, both in London and the IBA, who were responsible for erecting the transmitters, initially failed to get aerials up in time. A short term solution was provided by slinging an aerial between the chimney towers of a power station! As a result of this the new London stations earned themselves a derogatory name that tipped a hat to Radio Caroline, one of the best loved of the old pirate stations – Radio Clothes Line! The independent local radio (ILR) work that was given to the IBA was finally completed on time when the final one of the nineteen franchises, Beacon Radio went on the air in April 1976.

The next big change came with another rationalisation of the bands in 1989 – the Government decided that to double up output on AM and FM was inefficient and this yielded a range of new stations such as Capital Gold, LBC Talkback and Radio City Gold. The last ILR stations to receive normal licences were FM band stations in 1990 and this ushered in a scheme whereby new operators had to offer an additional type of service to what was already available – so a rock music station wouldn’t be allowed to start up if there were already several other locally available rock stations, but a talk based station, for example, would be favoured.

In 1990, ‘The Pips’ (the Greenwich Time Signal) moved from Greenwich to Broadcasting House and the BBC introduced its first new nationwide station since 1967 in the form of Radio Five on the AM band, to provide news, sport, talk and education a re-launch was arranged a few years later and the station reinvented itself as Five Live to provide news and sport. 1990 also brought deregulation to the commercial radio sector and more local and new regional licences were granted along with plans for three new national stations. The first of these was to be Classic FM in 1992, followed the next year by Virgin Radio on AM and Talk Radio UK in 1995. Radio One went fully over to FM in 1994 and their AM feed was switched off.

The work of construction, operation and maintenance of the BBC infrastructure (masts, transmitters etc) was subject to privatisation in 1996, bought by Castle Transmission International (analogue radio AM and FM) and Merlin Communications (short wave). The proceeds of these sales were invested in developing digital broadcasting.

Digital radio was seen as the key to the survival of radio, whereby the only possible strategy is to expand services into an ever increasing number of stations rather than maintaining and refining the quality of the existing, much-loved asset. The danger of this approach is that two things may be diluted in the process – quality and revenue. The Eureka Project team from the BBC and other European broadcasters developed a Digital Audio Broadcasting Standard (DAB) where the space on the band previously taken up by a single FM station can be occupied by the digitally compressed output of many stations (a multiplex) , so freeing up huge areas to host more stations. A lower resolution of the output will result in the ability to host more stations. Room was made for seven digital multiplexes, which could host up to 70 stations depending on the level of resolution selected. As time has gone on, the preferred resolution has decreased, meaning lower quality sound has been relinquished in favour of greater choice.

Only time will tell when or if DAB will take over from FM or even what form radio will take ultimately take in the future.

Chris Bennett

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