the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)-第4章
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
the same area； in spite of the fact that there had been some 'alleged'
solutions of the problem。 The phenomenon of resonance was known and
Dr （later Sir Oliver） Lodge had taken out various patents between 1889
and 1898 in connection with receivers。 Marconi and his assistants
ultimately solved the problem by modifying Lodge's syntonic Leyden jar
tuned circuit。 They added a tapped inductance in the aerial circuit of the
transmitter and used variable capacitors instead of fixed ones。 This was
probably the most significant modification made in the development of
wireless telegraphy。 （In Greek the word syntonismos 'to bring to equal
tone' is used for 'tuning'。）
Apart from the patents taken out by Sir Oliver Lodge and Dr
Alexander Muirhead； in 1897； patents were taken out in Germany by
Professor Braun of Strasbourg； who was joined by Professor Slaby and
Count D'Arco in 1903 to form the Telefunken company； and in the U。S。A。
by Dr Lee De Forest of the American De Forest Wireless Telegraph
Company who was the first to use a high A。C。 voltage of 20；000 volts to
obtain the necessary high…potential discharges； thus dispensing with the
induction coil。 Again in the U。S。A。； Professor R。O。Fessenden was
responsible for the design of new types of transmitting and receiving
apparatus。
During this period Marconi had resisted all offers by financiers to
acquire his patents。 In July 1897 he entrusted his cousin Jameson Davis to
form The Wireless Telegraph & Signal Company Ltd which soon became
Marconi's Wireless Telegraph Co。； and ultimately the Marconi Company。
William Preece of the Post Office detached one of his assistants；
George S。 Kemp； to help Marconi。 Kemp was destined to become his
right…hand man and served Marconi faithfully throughout his life。 By
today's standards； Marconi can be said to have been a highly successful
entrepreneur。 He had the great knack of selecting the right man for the job；
and inspired deep loyalty in his staff。 He regarded himself as an 'amateur'
and often paid tribute to the work of radio experimenters。
（Most of the above passages are quoted from 'A History of the
Marconi Company' by W。J。Baker； published by Methuen & Co Ltd。
reprinted in 1979。）
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
CHAPTER THREE
THE RADIO AMATEUR MOVEMENT
From the turn of the century enthusiastic young men who built their
own items of electrical and wireless apparatus were known as 〃Wireless
Experimenters〃。 Many of them were later granted licences for the use of
〃Wireless Telegraphy for experimental purposes〃 （in the United Kingdom）
by the Postmaster General under the terms of the 1904 Wireless
Telegraphy Act。 In his report to Parliament for the years 1905…1906 the
P。M。G。 stated that it was his wish 〃to promote experimental investigations
in this promising field〃。
In a book published in 1908 by R。P。Howgrave…Graham entitled
〃Wireless Telegraphy for Amateurs〃 the word amateur seems to have been
used for the first time。
During the 1914…1918 war all wireless apparatus in the possession of
licensed amateurs was closed down under the Defence of the Realm Act of
1914。 Experimental transmission licences numbered 1；600。
After the end of the war an Inter…Departmental Committee was set up
and in its report to the Postmaster General dated April 1919 it stated： 〃We
are of the opinion that the number of stations existing in July 1914 was
excessive from the point of view of government control in case of
emergency and the necessity of preventing interference with government
and commercial working； further there was no justification for it from the
point of view of the encouragement of research or development of
industry〃。
But there was a magnanimous relaxation in the Defence Regulations
when the Post Office notified manufacturers of electrical apparatus that
restriction on the sale of buzzers had been removed。 Buzzers could now be
sold without enquiry as to the use to which the purchaser proposed to put
them！！！
During 1919 many issues of WIRELESS WORLD considered 〃the
amateur position〃； and a leading article in the March issue began with a
quotation attributed to Marconi：
〃I consider that the existence of a body of independent and often
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
enthusiastic amateurs constitutes a valuable asset towards the further
development of wireless telegraphy。〃
In a subsequent letter to the Editor Marconi wrote：
〃In my opinion it would be a mistaken policy to introduce legislation
to prevent amateurs experimenting with wireless telegraphy （which the
authorities were contemplating）。 Had it not been for amateurs； wireless
telegraphy as a great world…fact might not have existed at all。 A great deal
of the development and progress of wireless telegraphy is due to the
efforts of amateurs。〃
John Ambrose Fleming； the inventor of the diode valve； also wrote to
the Editor of W。W。 as follows：
〃It is a matter of common knowledge that a large part of the
important inventions in connection with wireless telegraphy have been the
work of amateurs and private research and not the outcome of official
brains or the handiwork of military or naval organisations。 In fact we may
say that wireless telegraphy itself in its inception was an amateur product。
Numerous important inventions such as the crystal detector； the oscillating
valve； the triode valve have been due to private or amateur work。 If full
opportunities for such non…official research work are not restored； the
progress of the art of radio telegraphy and radio telephony will be greatly
hindered。〃
Professor W。H。Eccles wrote：
〃Improvements and invention must be stimulated to the utmost。 It is
not impossible to devise laws to impose restrictions upon the emission of
wireless waves as will preclude interference with the public radio service
of the future （R。F。I。 & T。V。I。？！！） and yet allow liberal opportunities for the
experimental study of wireless telegraphy。〃
NOTE。 The above passages are taken from WORLD AT THEIR
FINGERTIPS by John Clarricoats； O。B。E。；G6CL； published by the
R。S。G。B。 in 1968。
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
CHAPTER FOUR
THE 1921 TRANSATLANTIC TESTS
Most commercial experimental transmissions in wireless telegraphy
before World War I were carried out on the 〃long〃 wavelengths； though
they were not called that at the time。 Transmissions by amateurs in the
United Kingdom and the U。S。A。 on the other hand were made around 200
metres （1。5MHz）。 In the U。S。A。 amateurs were permitted to use a
D。C。input of 1；000 watts to the anode of the final stage of their
transmitters。 In the U。K。 the maximum power allowed was 10 watts and
the combined height and length of the transmitting aerial was not to
exceed 100 feet。 So when the first attempt to span the Atlantic was made
in February of 1921 it was natural that the American stations should do the
transmitting and the Europeans the listening。
About 25 U。S。 amateur stations participated in the tests； which took
place early in the morning on the 2nd； 4th and 6th of February 1921。
Although about 200 European stations had indicated their intention to
listen only 30 actually submitted logs。 And not a single one of them was
able to report hearing anything that could be attributed to the American
transmissions。
The then Editor of QST wrote： 〃We have tested most of the circuits
used by the Britishers and find them one and all decidedly inferior to our
standard American regenerative circuit using variometer tuning in
secondary and tertiary circuits。 We would bet our new Spring hat that if a
good U。S。 amateur with such a set and an Armstrong superheterodyne
could be sent to England； reception of the U。S。 transmissions would
straightaway become commonplace。〃 Strong language。
In September of the same year it was announced that a prominent U。S。
amateur Paul Godley 2ZE would be going to Europe to take part in the
second series of tests planned for December。 His expenses were being paid
by the A。R。R。L。 which already boasted having 15；000 transmitting
members。 In the U。S。A。 distances of over 2；000 miles had already been
achieved。
During his brief stay of a few hours in London Paul Godley was
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
introduced to Senator Marconi； to Admiral of the Fleet Sir Henry Jackson；
to Alan A。Campbell Swinton and many other distinguished members of
the Wireless Society of London； as the R。S。G。B。 was then called。
Paul Godley first set up his receiving equipment at Wembley Park；
Middlesex but soon decided that the electrical noises in the area would not
permit reception of the weak transatlantic signals。 He therefore obtained
permission to set up the European receiving station at
