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 of communication.
Fig. 321A - The Finch’s radio facsimilie system invented in the USA. (Communication).
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 321
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 to maximum.

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.