Broadcasting in Britain: The Formative Years 

25 November 2022 tbs.pm/76316

 

Cover of Broadcasting in Britain

From ‘Broadcasting in Britain’, published in 1972 by HMSO

Though ‘wireless telegraphy’ by Morse Code dates from 1896, the transmission of speech and music became practicable only during the 1914-18 War, when thermionic valves made it possible to vary the magnitude of a radio wave in proportion to the output signal from a microphone. Even then, the idea of using radio to entertain the general public seems to have occurred to very few people. However, when experimenters in ‘radio telephony’ began to enliven their transmissions with improvized entertainments, these were enthusiastically acclaimed by their audience of radio amateurs. Manufacturers then realized that there was, potentially, a mass market for receivers, and themselves began to radiate entertainment.

In Britain, the Marconi Company began such transmissions, from their works at Chelmsford, in February 1920; on June 15, in association with the Daily Mail, they radiated a recital by the famous soprano, Dame Nellie Melba, which aroused great public interest. In the autumn, however, the Post Office banned the transmissions, after complaints that they interfered with legitimate communication. It was over a year before the Post Office relented, in response to a petition from the amateur movement to allow Marconi’s to include telephony within their schedule of transmissions, ‘primarily to serve the scientific purpose of improving the receiving arrangements’. Fifteen minutes of telephony were to be permitted during a weekly half-hour of transmission for amateurs; the transmissions were, in fact, padded out to nearly one hour, by frequent compulsory breaks during which the station had to listen for possible instructions to give way to more important traffic.

Regular transmissions began on February 14, 1922, from ‘2 MT’, located in a hut at the Marconi field station at Writtle, near Chelmsford.

The 250-watt transmitter, powered by a petrol engine, was built from components that were at hand, by a team of young engineers who also put on the broadcasts as an out-of-hours chore. Each Tuesday, after reinstating any parts of the transmitters cannibalized for other work during the preceding week, they would radiate improvized programmes, made memorable by the comic talent of their senior member, P P Eckersley. Later in the year, the Post Office licensed three more transmitters, including another Marconi station; this was 2 LO, situated at Marconi House, London.

 

Marconi House

Marconi House, London, showing the aerial of the BBC’s first station ‘2 LO’ (1922-25): Early broadcasting transmitters were in towns and cities, to provide as many people as possible with the strong signal needed by crystal sets.

 

The Post Office’s extreme caution at this period was in part a reaction to the situation in America, where the experimental phase had led straight to a broadcasting ‘boom’; in the month of May 1922, for example, there were 99 additions to the list of stations. The result, of course, was a chaos of mutual interference.

The need to avoid a similar situation in Britain, by restricting the number of transmitters, was a prime consideration in the prolonged negotiations that took place during 1922 to thrash out a broadcasting system. The interested parties finally agreed that transmission should be in the hands of a monopoly — the British Broadcasting Company – whose profits were to be legally restricted to 71%, with capital subscribed by the British radio industry. Its income was to come from annual receiving licences and from a royalty on receivers, the import of foreign receivers being banned for two years.

The new company began regular broadcasting from 2 LO in London on November 14, 1922 to be joined the next day by 5 IT (previously operated by Western Electric) in Birmingham and 2 ZY (previously operated by Metropolitan Vickers) in Manchester. It was not until December, however, that the directors of the company appointed a General Manager, Mr J C W Reith, and it was not until February, 1923 that he in turn appointed a Chief Engineer, P P Eckersley. Nevertheless, by October of that year eight ‘main’ stations had been opened, substantially as laid down before the BBC was formed. They gave about 50% of the population of Great Britain a signal strong enough for clear reception on a crystal set.

 

A pianist and two singers

Broadcasting a duet from Marconi House (1922 or early 1923): The ‘telephone’ microphones then in use were designed for close speaking, so the two singers could not conveniently share the same microphone

 

Five Marconi engineers [Ashbridge, Bishop, Kirke, MacLartv and Wynn] who followed Eckersley to the BBC between 1923 and 1926 subsequently reached senior positions in its Engineering Division. But in 1923, to leave Marconi’s for the BBC was to abandon a career in the mainstream of radio communication, and to entrust one’s future to an organization seemingly devoted merely to the popularization of a technical hobby. In fact, as Eckersley foresaw, the future of broadcasting depended upon its outgrowing this ‘hobby’ status, and the BBC’s policy was to make reception of its programmes as easy as possible. In order to extend the service to large towns not covered by the ‘main’ stations, the BBC set up between November 1923 and the end of 1924 eleven ‘relay’ transmitters; these were of low power (100-200 watts), and their aerials were usually suspended between factory chimneys. For a modest outlay they increased to 70% the proportion of the population within ‘crystal range’ of a transmitter; many of the remaining 30% could receive a service if they used valve receivers.

Simultaneous broadcasting

With the opening of the Belfast station in 1924, the chain of nine ‘main’ stations was completed. Each station had its own studios, and initially originated all its own programmes. There were obvious advantages, however, in linking transmitters by telephone lines so that programmes could be shared, and ‘simultaneous broadcasting’ was introduced on a limited scale following experiments in May 1923. In the first experiment, the telephone lines were driven by a 40-watt public-address amplifier, to ensure an adequate signal at the far end. It was reported that, though the test was successful from a radio point of view, ‘… very considerable derangement in telephone trunk line traffic resulted.’

At that period, the telephone trunk network consisted of a mixture of underground cables and overhead lines, neither really suitable for broadcasting. The underground cables suffered from high-frequency loss, and the ‘loading’ technique that maintained adequate response up to a frequency of 2½ to 3 kHz (appropriate to a telephone circuit) caused a steep cut-off above that frequency. The routes used for broadcasting were therefore chosen to include as little underground cable as possible. The losses on overhead lines were lower and more uniform across the frequency band, but performance changed markedly with weather conditions; during the first quarter of 1930, an overhead line normally noted for its good performance averaged one reported fault for every five hours of programme carried. In addition, overhead lines were liable to be brought down by bad weather and road accidents.

The situation improved only in 1931 when the Post Office began transferring the ‘simultaneous broadcast’ network from overhead lines to selected underground circuits whose loading coils and repeater-amplifiers had been modified to give uniform response up to 6 kHz. By 1932, cables were coming into service that had been designed from the outset to handle broadcast programmes as well as telephony, and had a response extending to 8 kHz.

One of the first major applications of simultaneous broadcasting was in 1923-4, when the ‘relay’ stations were opened.

These originated very few programmes, and it had initially been intended that each station should take its programmes from the nearest ‘main’ station; in the event, however, local public opinion obliged the BBC to supply all relay stations with the London programme, notwithstanding the loss of quality resulting from long land-lines.

The first step towards extending broadcasting to the predominantly rural areas not covered by existing stations was the opening of a 25-kW long-wave transmitter (5 XX) at Daventry in July 1925, relaying the London programme. This was the most powerful broadcasting transmitter in the world, and the first to use long waves. Though other European countries followed Britain in setting up long-wave transmitters, America did not; their receivers thus had no long-wave band and the British receiver industry was effectively protected from American competition.

Because of the good long-distance propagation of long waves, and the great power of the transmitter, Daventry itself covered 55% of the population of Great Britain and brought 80% of the population within ‘crystal range’ of at least one transmitter.

Receivers

Valve receivers and loudspeakers were available from the beginning of broadcasting but the crystal set had two great advantages: it was cheap, and it was simple. It consisted basically of a tuned circuit and a crystal detector, and had no batteries, the power delivered to its headphones all coming from the transmitter. Most designs used a wire ‘cat’s whisker’ and the performance of the set depended upon making it touch a favourable spot on the crystal with just the right pressure; the slightest vibration spoiled the adjustment. Being devoid of any form of amplification, a crystal set was insensitive, and the sound was further weakened if several pairs of headphones were connected to the same set. Selectivity was poor – that is, the set could not separate transmissions of comparable strength unless their wave-lengths differed widely.

 

A crystal set

A crystal set of 1925: An alternative coil was plugged under the set for long-wave reception

 

But valve receivers were much more expensive: whereas a typical crystal set cost only one or two pounds [£65 to £130 today, allowing for inflation -Ed], a two-valve set was unlikely to cost less than £7 [£450], and a model with four or more valves could easily cost over £50 (1926 prices) [£3,300]. They also required batteries. The ‘low-tension’ accumulators used for heating the valve filaments were particularly inconvenient, requiring frequent re-charging at the local radio shop or garage. Even learning to operate a valve receiver could be a daunting prospect; one expensive receiver of 1923 was provided with two closely-printed pages of quite complex instructions. But the maker’s catalogue promised a rewarding performance: ‘… within fifty miles or so of a high-power broadcast station, music on the loudspeaker is so loud that it can be heard five hundred yards away.’

Early valve receivers depended for their sensitivity and selectivity upon ‘reaction’ – that is, upon feeding part of the output of a valve back to its input. If the reaction control were turned a little too far, the feedback was enough to maintain the valve in a state of oscillation, and the receiver effectively became a transmitter at a wavelength close to that of the station it was tuned to receive; that station was then spoiled by howling noises for everyone else in the neighbourhood. Stable amplification of the radio-frequency signal became straightforward only with the advent of the ‘screened-grid’ valve in about 1927.

 

The Mighty Atom Wireless Crystal Cats Whisker

Crystal-set accessories, about 1925

 

The listener’s licence entitled him to use 100 feet of wire in the construction of his aerial, and for satisfactory reception he needed to do so, unless he lived in a particularly favoured district or possessed one of the small minority of receivers offering satisfactory amplification before the ‘detector’ stage. Ideally, some 70 feet of the wire, secured by a porcelain insulator, ran horizontally towards the house from a tree, or a specially erected mast, in the garden. A stay-wire from the chimney stack, and another insulator, enabled the remaining 30 feet to run, steeply but not quite vertically, down to a ‘lead-in’ tube let into the window frame. The receiver was installed immediately inside the window, and the headphones or the separate loudspeaker connected to it by an appropriate length of wire.

An effective earth was also required; water pipes could be used, but a BBC article of 1928 recommends a metal plate 3 feet square, buried vertically in ground which, ‘if not naturally damp, can be made so artificially’.

Where a lower efficiency was acceptable, a frame aerial could be used. Apart from its convenience, it offered directionality which allowed discrimination against an interfering signal. Its very inefficiency made the frame aerial essential for a superhet receiver, which utilized an oscillator capable of radiating interference.

 

Large value radio and speaker horn

An early valve receiver (1923) with horn loudspeaker (1924): ‘Reaction’ was controlled by moving the coils at the left, and gain adjusted by switching vales in and out of circuit

 

Though the ‘hobby’ attitude to broadcasting was eventually to diminish, it flourished throughout the 1920s. Many people without previous experience of radio built their own receivers, by obeying the explicit instructions issued with kits of parts or published in such magazines as Wireless Constructor (circulation 250,000). Even those patronizingly dismissed by its editor as ‘ready-maders’ took pride in the number and remoteness of the foreign stations they could pick up.

The regional scheme

In 1925, when the increasing number of transmitters in Europe was causing serious interference, the BBC convened an international conference to discuss the problem, and drew up a provisional wavelength plan as a basis for discussion. The conference produced the so-called ‘Geneva Plan’, whereby Britain was allocated exclusive use of one long-wave and nine medium-wave channels. The BBC’s need to complete the coverage of rural areas and to provide an alternative programme could be reconciled with this plan only by abandoning the existing pattern of ‘main’ and ‘relay’ transmitters, sited in cities and towns.

 

Punch cartoon. Across 12 drawings, the radio hobbyist moves from one set to a complete buzzing room. Each picture is captioned: DO NOT DELAY - TO TAKE FULL ADVANTAGE - OF [RADIO'S] ENTERTAINMENT - FOR ONCE - YOU GET - BITTEN - WITH THE SUBJECT - YOU WILL - NEVER AGAIN - HAVE - MUCH - LEISURE FOR LISTENING.

 

In their place, five ‘twin-wave’ stations were built, each having two high-powered transmitters. The sites were chosen to achieve maximum coverage of each region, but centres of population were avoided in order to minimise the number of people receiving excessively strong signals.

The new type of station, providing two programmes at comparable strengths, hastened the disappearance of the crystal set. Though, in its advocacy of the regional scheme, the BBC had demonstrated to the Post Office that a well designed crystal set could in fact separate the two transmissions, in practice the survival of this type of receiver had largely rested upon the strong signal, on a single wavelength, near an urban transmitter.

 

Two masts and a transmitter hall

Twin-wave station at Washford Cross, Somerset (1933): The BBC’s ‘regional scheme’ provided for five high-powered stations, each radiating two programmes over a wide area.

 

Microphones and studios

Before broadcasting began, virtually the only microphones were those used in telephones, designed to transmit a limited range of frequencies, and to be held close to the mouth. The earliest broadcasts were, in fact, made with the aid of such microphones, sometimes with a small horn added to increase sensitivity.

The first microphone adopted for use throughout the BBC was the Marconi-Sykes ‘Magnetophone’. This was a moving-coil instrument in which the sound impinged directly upon a flat coil of aluminium wire, which was mounted within the field of a strong electromagnet by being stuck on to pads of cotton wool with ‘Vaseline’; a disadvantage of the design was the tendency for the coil to drop off during transmission. The microphone was slung on foam rubber within a large ‘meat-safe’.

 

Spacious studio with a piano in it

‘Drama’ studio at Savoy Hill, 1928: A late example of a heavily-draped studio using a ‘meatsafe’ microphone

 

The large size of this microphone caused its coil to be shaded from high-frequency sound coming from the side or from the rear, imparting a ‘boomy’ quality to reverberant sound and thereby aggravating excess low-frequency reverberation, the most common acoustic fault of small studios. As an antidote, early studios were heavily draped to suppress reverberation altogether, though this made them unsympathetic to the performer and uninteresting to the listener. Artificial reverberation was sometimes added, by means of a loudspeaker and microphone situated in a highly reverberant room, separate from the studio.

 

Wooden control desk in a room with a sofa and an easy chair by a fireplace

‘Musical control’, Savoy Hill, 1930: The decor was intended to ensure that the sound quality was suited to domestic listening conditions

 

The Marconi-Reisz carbon microphone, introduced in 1926, was much smaller, and had a more uniform frequency response; despite its slight background hiss, and a tendency to distort loud sounds, the BBC used it almost exclusively from about 1928-32, both in the studio and for outside broadcasts.

Outside broadcasting

From the earliest days, studio programmes were supplemented by outside events; operas were relayed from Covent Garden, dance bands from the Savoy Hotel, religious services from St Martin-in-the-Fields.

In April 1924, King George V made his first broadcast, during the opening of the British Empire Exhibition at Wembley. The programme was transmitted by all BBC stations, and the Daily Mail made arrangements for loudspeaker relays to crowds throughout the kingdom; it was estimated that nearly ten million people heard the broadcast. On an evening in the following month, there began a memorable series of broadcasts of the ’cellist, Beatrice Harrison, playing in her garden and being answered by the song of a nightingale.

Outside broadcasting taught engineers how to cope with all types of acoustics; for example, relays from the Palm Court of the Grand Hotel, Eastbourne, successfully conveyed its distinctive ‘live’ quality. Land-lines back to the studio were, literally, a weak link; most were in underground cables with a restricted frequency response, and might at any moment become noisy, making it necessary to substitute a stand-by line.

So long as the BBC remained a private company, newspaper interests successfully opposed the broadcasting of sporting events, but when the Company became a public Corporation on January 1st, 1927, the restrictions were lifted, and during that year running commentaries on many events were broadcast for the first time, including the Boat Race, the Cup Final, the Derby and the Wimbledon finals.

Empire broadcasting

Until the mid 1920s, long-distance radio communication was achieved by the use of very long wavelengths, comprising too narrow a range of frequencies to be of use for broadcasting. The situation was completely transformed, however, by the discovery that wavelengths of 100 metres and less could reach distant points by reflection from the ionosphere – the layer of ionized particles constituting the uppermost part of the earth’s atmosphere. Within a very short time, the Marconi company established a network of short-wave ‘beam’ stations. This development opened up the prospect of the BBC’s providing an English-language service to the Empire, but the feasibility of short-wave broadcasting could not be assumed from the success of point-to-point short-wave communication. The signals would have to be picked up by simple aerials feeding domestic receivers, whilst the large areas to be covered limited the extent to which the transmissions could be ‘beamed’. Moreover, reception would have to be good enough to sustain the listener’s interest, often in competition with locally transmitted programmes. In 1927, therefore, the BBC initiated tests, in collaboration with the Marconi company, from a 25-kW transmitter at Chelmsford. The transmissions were restricted to a single wavelength – 24 metres – and were not beamed, but results were nevertheless good enough for the BBC to propose, in 1929, the construction of a more ambitious experimental station at Daventry. At this time of great economic depression, however, neither the British Government nor the Empire countries would finance the scheme, and it languished until November 1931, when the BBC undertook to proceed with Empire broadcasting at its own expense. The Daventry station was opened in December 1932; it was equipped with two transmitters and eleven aerials (five directional and six non-directional), and was able to use eight different wavelengths.

The Blattnerphone

Empire broadcasting created an urgent need for sound-recording facilities, so that programmes could be transmitted to each time-zone in turn. Gramophone recording would not serve, being too expensive for everyday use, and involving a delay of at least twelve hours while the discs were processed, thus preventing the transmission of topical items.

The only machine at that time capable of providing direct playback was a magnetic recorder of German manufacture. The BBC had shown interest in the original version, an office dictating-machine invented by a Dr Stille, as early as 1925, but had found its quality inadequate for broadcasting. By 1929, however, Louis Blattner had undertaken exploitation of the machine in this country, had named it the ‘Blattnerphone’, and had improved it to the point where the BBC was interested in an operational trial, which began in 1930. The quality of reproduction, particularly the constancy of pitch, was not good enough for music recording, and a typical application was the repetition, in an evening news bulletin, of a speech or running commentary recorded earlier in the day.

The Blattnerphone was the forerunner of the modern tape recorder, in so far as it involved magnetic recording on a tape. The tape, however, was of steel, 0.08 mm thick, and ran at a speed of about 150 centimetres per second, so that a half-hour programme required a massive spool containing nearly three kilometres of tape. Editing was possible, but involved soldering or welding the tapes, whilst any irregularity in the tape surface could damage the recording or playback heads. Despite these shortcomings, use of the Blattnerphone in the BBC’s domestic services gradually increased and the Empire service made great use of it from the outset.

Broadcasting House

For its first London studio, the BBC made use of a small room in Marconi House, in the Strand, but on May 1, 1923 moved to spare accommodation at the Institution of Electrical Engineers building on the embankment. By 1927, this ‘Savoy Hill’ site was developed to its limit. The total of seven studios would clearly be insufficient for the two independent programmes that the ‘regional scheme’ was to provide, and in 1928 the Corporation completed arrangements to build new headquarters, to be known as ‘Broadcasting House’, on a site near Oxford Circus. The BBC initially considered that it would not need to occupy the entire building, and planned to lease the ground floor frontage as shops, though in the event this idea was dropped. Broadcasting House was opened in May 1932. It was tall by the standards of the period, having eight storeys above the ground floor and three below it. Its twenty-two studios, including a concert hall with seating for an audience of 724, were contained in a central tower within the building, to ensure adequate insulation from traffic noise; this studio tower was built of brick to avoid sound conduction from the steel-framed office accommodation surrounding it. Studios on different storeys were insulated from each other by interposing rooms such as music libraries and book stores. A sophisticated air-conditioning system controlled temperature and humidity.

Many of the studios were designed for specific purposes. The ‘vaudeville’ studio was provided with spotlights for the artistes and tiny ‘pit’ and ‘gallery’ seating areas for a studio audience. On the third floor was a ‘religious service’ studio, complete with ‘altar’, while one of the talks studios was made to look like a library’, for the reassurance of speakers who might have been frightened by the functionalism prevailing in other studios. The sixth floor ‘drama’ suite included an elaborate ‘effects’ studio.

No studio was self-contained, the amplifiers for all microphones being situated in the building’s main control room. The programme was controlled primarily from this room, or from a control panel equally remote from the studio itself; any ‘mixing’ of a studio’s various microphones was, however, done from its adjoining listening room.

This imposing building reflected the status that broadcasting had acquired in its first ten years. The number of receiving licences passed five million during 1932, and the receiver industry estimated that fifty million pounds’ worth of business would result from that year’s Radio Show at Olympia.

 

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