|Fig. 321 - An early type of facsimilie machine.
As aforementioned after so many researches it has been in the beginning
of XX century only that the first reliable facsimile transmissions
systems were capable to transmit high quality images.
In Germany, Arthur Korn invented a facsimile system originally based
in the Bidwell’s principle where the photograph was scanned
directly by a selenium photocell.
Later German police in the law enforcement to transmit either photographs
as well as fingerprints from outlaws used the Korn system.
In 1904, Edouard Belin, a french inventor, was awarded with a patent
for a system where firstly the photograph should be turned into
a relief etching, arisen a profile with the image details. Then
a stylus connected to a variable resistance in such away the deeper
the cut scanned the relief etching, the more current flowed.
In 1907, in France while Belin succeeded in transmitting a potograph
in the circuit Paris-Bordeaux, Korn used his system from Paris to
London, thus, giving birth to the first international facsimilie.
The need for very high quality photographs for publication in newspapers
kept a constant pressure on the development and improvement in the
two aforementioned systems originating a fast and reliable mean
The facsimilie transmission system was so important that in 1935,
in the USA, H.G.Finch invented a home facsimilie machine, which
could be esily connected to a general radio receiver. By tuning
a broadcasting radio station the listener caould receive in his
home the “picturegram”, later known a radiophoto. Fig
|Fig. 321A - The Finch’s radio facsimilie
system invented in the USA. (Communication).
Basically the Finch system comprised a transmitter provided with
a scanning machine in which the copy to be sent over the air was
inserted in what is known as a copy head. The scanning head comprised
an electro-mechanical system. The light from the bulb was focused,
as a small spot, on the surface of the paper carrying the copy and
the reflected light was picked up by a photocell. The scanning head
was moved from side to side in such away the spot of light traced
a series of parallel paths covering the entire surface; i.e. line-by-line,
either the black, half-tone as well as the white areas which were
collected by the photocell whose amount of light ranging from minimum
|Fig. 321B - An early type of facsimilie transmission
circa 1930. The “picturegram” was transmitted from
London to New York and illustrate an armored car used by the
British army to garnish a street in London during a strike.
Those variations in the reflected light effected a change in the
amount of electric current flowing through the photocell which in
turn generated a high pitched whistle-like tone as known as facsimilie
carrier, which then was sent to an ordinary broadcast amplifier.
In this way, since no adjustment were necessary to attain maximum
definition other than the optical line-up, bias and carrier-tone
adjustment, any conventional receiver tuned in the frequency of
the transmitter will then pick up the signal. However, in order
to convert those signals back to a visible copy it was mandatory
a recording machine connected the receiver itself.
Just after WWI, the domestic home radio receiver suffered many improvements
gathering its advanced industrial design with an excellent performance
either in signal reception as well in sound reproduction. In the
mean time, the frequency modulation broadcasting system brought
new technologies in sound recording as: the magnetic tape and the
microgroove record, also known as “Long Playing”, stimulating
the consumer to have in his living room a new family of equipments
for sound reproduction in high fidelity.