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This is a brief history of radio development,
starting from the early years to the time when radio manufacturing ended
at Wolverhampton. Any description of the developments will inevitably be
of a technical nature. Actual descriptions of some of the circuits have
been included, but these are separate to the main text, so if you are
not interested in the technicalities, they can be ignored.
Beginnings
James Clerk Maxwell, the Scottish physicist, was
born on the 13th of June 1831, in Edinburgh. He was very interested in
Michael Faraday’s work on electromagnetism. Faraday explained that
electric and magnetic effects result from lines of force that surround
conductors and magnets. Maxwell drew an analogy between the behaviour of
the lines of force and the flow of a liquid, deriving equations that
represent electric and magnetic effects. In 1855 he produced a paper
which built on Faraday’s ideas, and in 1861 developed a model for a
hypothetical medium, that consisted of a fluid which could carry
electric and magnetic effects. He also considered what would happen if
the fluid became elastic and a charge was applied to it. This would set
up a disturbance in the fluid, which would produce waves that would
travel through the medium. The German physicists Friedrich Kohlrausch
and Wilhelm Weber calculated that these waves would travel at the speed
of light. Maxwell finally published this work in his ‘Treatise on
Electricity and Magnetism’ in 1873.
In
1888 German physicist Heinrich Hertz made the sensational discovery of
radio waves, a form of electromagnetic radiation with wavelengths too
long for our eyes to see, confirming Maxwell's ideas. He devised a
transmitting oscillator, which radiated radio waves, and detected them
using a metal loop with a gap at one side. When the loop was placed
within the transmitter’s electromagnetic field, sparks were produced
across the gap. This proved that electromagnetic waves could be sent out
into space, and be remotely detected. These waves were known as
‘Hertzian Waves’ and Hertz managed to detect them across the length
of his laboratory.
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Guglielmo Marconi and his family in
1933
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Italian
born Guglielmo Marconi was fascinated by Hertz’s
discovery, and realised that if radio waves could be transmitted
and detected over long distances, wireless telegraphy could be
developed. He started experimenting in 1894 and set up rough
aerials on opposite sides of the family garden. He managed to
receive signals over a distance of 100 metres, and by the end of
1895 had extended the distance to over a mile. He approached the
Italian Ministry of Posts and Telegraphs, informing them of his
experiments. The Ministry was not interested and so his cousin,
Henry Jameson-Davis arranged an interview with Nyilliam Preece,
who was Engineer-in-Chief to the British Post Office.
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He
came to England in February 1896 and gave demonstrations in
London at the General Post Office Building. His transmissions
were detected 1.5 miles away, and on 2nd September at
Salisbury plain the range was increased to 8 miles. In 1897 he
obtained a patent for wireless telegraphy, and established the
Wireless Telegraph and Signal Company at Chelmsford. The
world’s first radio factory was opened there in 1898. On 11th
May 1897 tests were carried out to establish that contacts were
possible over water. A transmitter was set up at Lavernock
Point, near Penarth and the transmissions were received on the
other side of the Bristol Channel at the Island of Holm, a
distance of 3.5 miles. The Daily Express was the first newspaper
to obtain news by wireless telegraphy in August 1898, and in
December of that year communication was set up between Queen
Victoria’s Royal yacht, off Cowes and Osborne House. The Queen
received regular bulletins on the Prince of Wales’ health, by
radio, from the yacht, where he was convalescing.
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An early Marconi transmitter
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Also
in December of that year, wireless communication was set up between the
East Goodwin light ship and the South Foeland lighthouse. On 3rd
March 1899 Marconi obtained a lot of publicity when the first life was
saved by wireless telegraphy, which was used to save a ship in distress
in the North Sea. By the summer cross channel communication had been
established and the first ocean newspaper published bulletins sent by
wireless.
About
this time Marconi began to develop tuned circuits for wireless
transmission, so that a wireless can be tuned to a particular frequency,
to remove all other transmissions except the one of interest. He
patented this on 26th April 1900, under the name of ‘Tuned
Syntonic Telegraphy’.
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The transmitter at Poldhu
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On
Thursday 12th December 1901, Marconi and his
associates succeeded in transmitting a signal across the
Atlantic Ocean. He sailed to Newfoundland with G.S. Kemp and
P.W. Paget, and received a transmission from Poldhu, Cornwall.
The transmission was received at Signal Hill using a kite
aerial. The British government and admiralty were greatly
impressed and many people wanted to invest in the new
technology.
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Demand
grew and large numbers of ships carried the new apparatus, which saved
many lives at sea. One of the most famous occasions was when the Titanic
sank. Signals transmitted by its Marconi wireless summoned help and
saved many lives.
Receivers
at this time were mainly crystal sets, which were extremely insensitive
and unselective. They were connected to a pair of headphones and
required a long aerial.
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Descriptions of the Early Transmitters and Receivers
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At
this time wireless was strictly controlled by the Post Office. It was a
simple matter to obtain a receiving licence but much more difficult to
obtain permission to use a transmitter. In order to do so the Post
Office had to be satisfied that the applicant had suitable engineering
qualifications, or knowledge to operate the transmitter. Transmitter
output power was restricted to ten watts, and use was only permitted for
scientific research or for something of use to the public. A small
number of radio amateurs were transmitting before the first world war.
We had at least two in Wolverhampton; Harry Stevens of Oaklands Road and
Mr. J. Vincent Waine of Helmsley Lodge, Wednesfield.
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One of Mr. Waine's aerials.
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Mr.
Waine, who began transmitting in about 1898 became well known
locally when he received the S.O.S. that was transmitted by the
Narrung P.&O. liner, during a gale in the Channel, on Boxing
Day 1912. Wireless was his main hobby, he was an enthusiastic
amateur and recorded messages from places as far as Russia,
Austria, Hungary, Italy, Africa and America. He designed and
built all of his transmitting and receiving equipment, including
a spark gap transmitter and a special sensitive detector. He was
never satisfied with the equipment and always strived to improve
its performance. Mr. Waine's call sign was 'ZAX'. The three
aerials in his back garden used something like 3,000ft of wire.
The equipment was housed in a cupboard in the dining room so
that it could be operated in comfort.
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Mr
Waine also had links with commercial radio companies and was
associated with Marconi, Dr. Fleming and Sir Henry Jackson, who
was Admiral of the Fleet. He also gave financial assistance to
Mr. John Logie Baird the television pioneer.
The
opposite photograph shows Mr. Waine's indoor equipment.
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Mr.
Waine's eight and a half year old son, Vincent, was also a keen
radio enthusiast and eagerly used his father's equipment. He
possessed a miniature wireless set capable of receiving and
transmitting over three miles.
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Mr.
Waine and his family acquired the Point of Air Lighthouse, at
the mouth of the River Dee, as a weekend holiday home, in the
early 1930's. As well as a weekend retreat it was used as a base
for much of his experimental work.
The
photograph opposite shows Mr. Waine and Vincent receiving a
message.
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I would like to
thank Peter Waine for the information about his father's wireless
station.
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Proceed
to the Valve Era
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Return
to the List of Manufacturers
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