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Facsimile — Radiofax
Facsimile (from latin facere – make and simile – similar) is one of the oldest communication modes and it is used for an image transmission. The facsimile is mainly
used by professional services for wireless distribution of meteorological maps and
informations, hence the name Weather Facsimile (WEFAX) follows from it. The
radiofax can be used by radio amateurs too.
11.1 The history of image transmission
Already in 1843 a Scottish clockmaker Alexander Bain suggested that some images
can be broadcast via electric lines, when it is electrically scanned by rows and point
by point. That’s the basic idea of image transmission.
Bain’s example was soon followed by other entrepreneurs. In 1847 an Englishman
Frederick Collier Bakewell reeled an image in the transmitter and sheet of paper to
cylinder in the receiver, which was turned by the clock machine. The picture were
printed with fat on a tinfoil sheet.
Figure 11.1: Bakewell’s
image telegraph.
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