The dawn of radio
The BBC opened the first regular public broacasting station in the world on 14th November 1922 in London. Stations in
Birmingham and Manchester opened the following day, followed by Newcastle on 24th December, Cardiff on the 13th February
1923, Glasgow on the 6th March, Aberdeen on 10th October and Bournemouth on 17th October. These stations all broadcast at
1.5 kW, though London was increased to 3 kW in Match 1925 when the transmitter was moved to Selfridges.
This is a relatively low power by modern standards, so many cities were left with poor reception. So, from November 1923
to December 1924, 100 W relays were introduced for Bradford, Dundee, Edinburgh, Hull, Leeds, Liverpool, Nottingham,
Plymouth, Sheffield, Stoke and Swansea, together with a 1.5 kW transmitter for Belfast. At that time, the medium wave band
extended only from 600 to 1000 kHz and each station was on a different frequency.
In October 1926, a 25 kW long wave station was opened at Daventry on 187.5 kHz (1600 metres). This filled in most of the
coverage gaps in Central and Southern England, bringing a radio service to Norwich for the first time and improving
reception in places like Oxford, Leicester, Cambridge and Ipswich. However, listeners would have had to buy a new
radio. In August 1927, the first high power medium wave transmitter was opened, also at Daventry, replacing Birmingham and
Nottingham and extending coverage to much of East Anglia.
On 14th November 1926, the first of many international re-plans of the medium wave band was made, extending it up to
1200 kHz and implementing 10 kHz channel spacing. Following this, some of the BBCs relays in different parts of the
country shared a common frequency. Two further re-plans were made on 13th January and 30th June 1929, extending the medium
wave band to 1500 kHz and abandoning the 10 kHz channel spacing. In this plan, frequencies were allocated to countries
instead of to individual transmitting stations.
The National and Regional Programmes
Through the 1930s, the BBC gradually replaced its transmitter network with new high power stations located outside the
cities, broadcasting at powers between 40 and 100 kW. The next station to be opened after Daventry was Brookmans Park in
Hertfordshire on 21st October 1929, serving London, the South East and parts of East Anglia, and replacing the 3 kW
transmitter at Selfridges. On the opening of a second high power transmitter at Brookmans Park on 9th March 1930, a second
programme was introduced for the London and Midland regions. At Daventry, the National Programme was carried on long wave,
extending to parts of the south and some northern cities, while the Regional Programme was carried on medium wave. At
Brookmans Park, both programmes were transmitted on medium wave, with the lower frequency, giving higher coverage,
allocated to the Regional Programme.
The next high power transmitter opened was Moorside Edge on the Pennines, replacing the main station at Manchester and the
relays at Bradford, Hull, Leeds, Liverpool, Sheffield and Stoke. The Regional Programme opened on the 17th May 1931, with
the National Programme following on 12th July. This was followed by Westerglen in Central Scotland, replacing Glasgow,
Edinburgh and Dundee, which opened with both programmes on 12 June 1932. The next year, the Washford transmitter by the
Somerset coast was opened, replacing Cardiff and Swansea and also covering much of Western England. The Welsh Regional
Programme opened on 28th May 1933, with the National Programme following on 17th July and using the same frequency as that
programme from Brookmans Park.
On the 15th January 1934, another international frequency plan was implemented, resulting in more changes to the BBC
frequencies, including the long wave transmitter moving to 200 kHz. This plan was to last until 1950. In October of 1924,
a new 150 kW long wave transmitter for the National Programme was opened at Droitwich, south of Birmingham, replacing the
25 kW station at Daventry and covering most of England and Wales. The Regional Programme moved to Droitwich on 17th
January 1935, which was accompanied by many of the BBCs transmitters exchanging frequencies, including the National
Programme at Moorside Edge joining Brookmans Park and Washford on 1149 kHz.
In 1936 and 1937, high power transmitters opened at Lisnargarvey for Northern Ireland, Stagshaw for the North East and
Cumbria and Burghead for Northern Scotland, each carrying the Regional Programme only. A smaller 5 kW transmitter was
opened at Penmon to bring the Welsh Regional Programme to North Wales and Aberdeen was replaced by a 5 kW transmitter at
Redmoss. With the National Programme now available on long wave, the transmitter at Washford was re-allocated to provide a
Western Regional Programme, supplemented by the old transmitters at Bournemouth and Plymouth. In June of 1939, the Western
Regional transmitters were replaced by a 100 kW transmitter at Start Point in Devon and a 20 kW transmitter at Clevedon,
near Bristol, enabling the last of the original transmitting stations to be closed.
In the 1930s, the BBC was subjected to competition for the first time. From 1931, French station Radio Normandie began
broadcasting in English after its local programmes had finished. In 1933, Radio Luxembourg opened a 200 kW long wave
transmitter, broadcasting in English from the Grand Duchy in the afternoons and evenings.
The war years
When war broke out, enemy bombers using radio transmitters for navigation became a potential problem. To combat this, the
long wave transmitter was closed and the medium wave transmitters grouped into three synchronous groups of four on the same
frequency. Initially, two frequencies were used to broadcast the Home Service, which replaced the National and Regional
Programmes, to northern and southern Britain, whilst a third frequency was used to broadcast the European Programme at night.
By October 1941, Start Point had been converted to horizontal polarisation to prevent its use for direction finding and the
Droitwich long wave transmitter converted to a high power medium wave station. These took over the broadcasting of the
European Programme, freeing up transmitters for a new Forces Programme.
The synchronous transmitters not only interfered with each other in areas where the signal strengths were similar, but had
to be switched off during air raids. To improve reception of the Home Service, a synchronous network of 61 low power
transmitters, known as Matrix H, was constructed on 1474 kHz. More details are given in an article on
MB21. As the war progessed, further transmitters were opened
to boost reception of all three services, including extra European Programme transmitters at Crowborough in Sussex and
Ottringham, East Yorkshire.
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The dawn of radio
National and Regional
The war years
Home, Light and Third
The birth of FM
The pirates
Radios 1-4 & Local Radio
Splits & AM re-shuffles
Improving FM
Commercial radio expands
Going digital
R1 transmission history
Classic Radio 1 Schedules
Virgin Radio launch
Eduational Radio
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