Reginald Aubrey Fessenden
- an overview of the life and work of RA Fessenden the Canadian inventor and
radio pioneer.
The name of Reginald Aubrey Fessenden is not as widely known
as it deserves. Also he is often quoted as being an American, a fact which
Canadians hotly contest as Fessenden was born in Canada. In his life, R A
Fessenden achieved a considerable amount, pushing back the frontiers of radio or
wireless technology of the day. He held many firsts, and without his drive and
insight, radio technology would have developed considerably more slowly than it
did.
Fessenden's most notable achievements include the first audio
radio transmission in 1900, the first two way transatlantic transmission in 1906
and the first broadcast of entertainment, also in 1906. Many of these were well
ahead of their time, and showed his insight, not only into the technical aspects
of radio, but also the commercial elements as well.
Fessenden's early years
Reginald Aubrey Fessenden was born on 6th October 1866 in the town on East
Bolton, Quebec, Canada. He was the eldest of the four children of Elisha and
Clementina Fesseden. His mother was a minister in the Church of England in
Canada and as a result the family moved several times during RA Fesseden's
childhood.
The young Reginald Fessenden was intelligent and was able to
learn quickly. In 1877, at the age of 12, he entered Trinity College in Port
Hope Ontario, and two years later he moved to Bishop's College (now Bishop's
University) in Lennoxville, Quebec. However Fessenden left at the age of 18
having nearly completed his degree, but not gaining the final award.
As a result of leaving Bishop's College with no formal
qualification, Fessenden found it more difficult to move forward. However he
managed to secure a position at Whitney Institute in Bermuda as the sole teacher
and principal. While he was in Bermuda he became friendly with Helen Trott to
whom he later became engaged and in September 1890 they were married.
Work begins
Although Fessenden had been granted a mathematical scolarship at Bishop's
College, much of his education had a classics orientation and this did not suit
him for a career in the new and developing area of electrical sciences. To
improve his chances of success, he moved to New York in 1886 with the hope that
he might be able to secure some employment with Edison's company. His initial
attempts were unsuccessful, but after pursuing opportunities with Edison he was
hired as an assistant tester for the Edison Machine Works, a company laying
underground electrical mains cables in New York.
Fessenden showed an aptitude and keenness for the work and
was promoted so that in 1886 he started to work directly for Edison himself at
the new "invention factory" as it was termed at West Orange , New Jersey. Here
Fessenden was involved in a number of sciences and he soon gained a considerable
degree of experience.
Unfortunately the Edison company faced severe financial
problems in 1890 and had to lay off a large number of employees and Fessenden
was included in this number.
As a result of his experience with Edison, Fessenden was able
to find employment relatively easily. He worked for a number of companies, but
in 1892 was appointed as professor at the newly formed Department of Electrical
Engineering at Purdue University in Indiana. Later he moved from here to the
Western University of Pennsylvania, which is now the University of Pittsburgh.
Work at the Weather Bureau
During the late 1890s Marconi started to hit the headlines with his experiments
that were pushing back the frontiers of wireless transmission technology.
Marconi was something of a showman and was able to capture the news headlines.
Reginald Fessenden too, started to become interested in wireless technology and
as a result he started his own experimentation in this field, initially looking
at some of the equipment used.
The possibilities that early wireless technology appeared to
offer fascinated Fessenden. In 1900 he left Pittsburgh to work for the United
States Weather Bureau. Fessenden saw the possibility of using wireless
transmissions to link a network of coastal stations together rather than using a
wired telegraph link. For his work, Fessenden was based at Cobb Island on the
Potomac River in Maryland
Fessenden made several major advances, in particular in the
area of receiver design as this was one of the major limitations of the time. He
first developed a new form of detector known as the barretter detector, and this
was followed by the electrolytic detector which remained in used for many years.
Another major milestone, during this period was that
Fessenden succeeded in making what is believed to be the first wireless
transmission carrying audio sound. The experiment took place on 23rd December
1900 and the signal was received over a mile away.
The equipment used by Fessenden was a spark transmitter with
an interrupted to provide a continuous series of sparks. The output of the
generator was modulated by placing a carbon microphone directly in the antenna
lead. Although very crude by today's standards, the system nevertheless worked.
It is reported that using the transmitter Fessenden spoke loudly into the
microphone saying: "Hello test, one ,two, three, four. Is it snowing where you
are Mr Thiessen? If it is telegraph back and let me know." His assistant
immediately returned a telegraph message to indicate he had heard Fessenden and
that it was also snowing, which was hardly suprising as he was only a mile away.
The received signal was described as being perfectly understandable, except that
it was accompanied by a loud disagreeable noise resulting from the irregularity
of the spark.
Fessenden worked to improve the system over the following two
years and more. By 1903 he had succeeded in obtaining reasonably satisfactory
speech transmission by creating an almost continuous arc. However the system was
still plagued by the very unpleasant sound of the arc itself.
Heterodyne principle
One of the other major advances made by Fessenden was the development of the
heterodyne principle. He undertook experiments with this in 1901, but in view of
the state of wireless technology, it was well ahead of its time and was not used
for over ten years afterwards as it required the generation of stable continuous
wave signals and these were not practicable until the thermionic valve or vacuum
tube became available.
The network of wireless stations expanded and started to
prove its worth. However during this time legal arguments started over the
possession of the patents. As a result of this, Fessenden's time at the Weather
Bureau came to an end in August 1902.
NESCO
The work that Reginald Fessenden had undertaken at the Weather Bureau had not
gone un-noticed. Some saw the value of the work that he had undertaken and
sought to enable him to carry it on. Hay Walker Jr, and Thomas Given financed
the formation of a company named National Electric Signalling Company based in
Massachusetts. Under the auspices of this company, Fessenden would be able to
carry out research into several projects that would have a variety of
applications.
As part of the development programme for long distance
communications it was decided to set stations that would enable the first two
way transatlantic contact to be established and a service to be introduced
thereafter. Although Marconi had made the first transatlantic transmission in
1901, the transmission was only in one direction. Stations were set up at Brant
Rock in the USA and another in Scotland at a location named Macrihanish. The
result was that in January 1906 the first two way transatlantic communication
was established. Unfortunately the full commercial service was not able to be
introduced because the tower collapsed on 6th December 1906 when contractors
were working on the steel guy ropes. The investment required to re-establish the
station was felt to be too large and the service was abandoned.
Another major area of work was the development of a high
frequency alternator. This would be able to provide a means of generating a
continuous wave signal. Fessenden had first worked on the idea in 1900 and even
when the first device was delivered in 1903 it would only operate up to a
frequency of 10 kHz. A second alternator was ordered and eventually delivered in
1905, and the company that made it stated that it would not operate above 10
kHz. As a result Fessenden himself set about building an alternator that would
operate at the frequencies he wanted. He used some parts of the one that was
delivered to him and by late 1906 he had a machine that would operate at 75 kHz
and developed an output power of 500 watts. This enabled him to transmit the
continuous wave signals he needed.
Fessenden modulated his HF alternators in the same way he had
his previous transmitters by placing a carbon microphone in the antenna lead.
One night in November 1906 the station at Brant Rock was in communication with
another at Plymouth, MA, USA. However this transmission was heard on the other
side of the Atlantic in Macrihanish. Then on 24th December 1904 Fessenden and
his assistants presented the first radio broadcast. The broadcast included a
speech by Fessenden along with him playing Handel's Largo in the violin. The
broadcast was heard by stations as far away as the West Indies, and it was
repeated n New Year's eve.
After NESCO
After Fessenden left NESCO he did not work directly on radio again, but he did
continue to work on other projects and inventions. He became particularly
interested in Sonar and in methods of detecting icebergs. At the outbreak of
World War 1 he volunteered his services to the Canadian Government worked in
London England on methods of detecting artillery, as well as means to detect
enemy submarines.
After the war he continued to investigate a wide variety of
ideas, refining some of his work on sonar as well as investigating seismology
for oil wells, and inventing a fathometer.
As a result of his work, Reginald Fessenden held over 250
patents, but despite this his name was never really given the recognition that
it should have received. However he did receive the Scientific American Gold
medal in 1929.
Last years
Fessenden managed to settle a lawsuit with RCA over patent rights and using the
money he gained he bought a small estate on the island of Bermuda where he spent
the rest of his days. He died there in 1932 and is interred in the cemetery of
St Mark's Church.
Reginald Fessenden is certainly one of the unsung pioneers of
wireless and radio technology. Although Marconi received much of the limelight
with his work, Fessenden had a might greater insight into the workings of radio
technology. He achieved many "firsts". He was the first to develop a method of
generating a continuous wave signal and to use it. He was the first to transmit
voice, and to make a sound broadcast. He developed and was the first to use the
hererodyne principle that forms the basis of almost every radio today. He was
the first to establish two-way communication across the Atlantic, and to send a
voice signal across the Atlantic. In many ways, Reginald Fessenden made huge
contributions to the technology of radio, and yet he is comparatively little
known. Even when people do recognise his name, he is often thought of as an
American, whereas in fact he came from Canada.
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