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Radiotelephone leaflet, 1927

Using the radio telephone : bridging the last gap

The development of radiotelephony made it possible to telephone the USA directly from 1927 onwards.

This was a very expensive service, priced out of reach of all but businessmen and the wealthiest socilaites.
The impact on the telephone industry in general was slight - but the impact on business was quite profound.

The new transatlantic service was charged by three minute units, with all calls being placed 'person to person' - you only made the call if the operator could locate your chosen party and bring them to the telephone, being allowed one call at a time.

Before the 1920s were over, there were four radiotelephone links to New York - and 94 international telephone circuits worldwide. But you had to be in or close to London to use the new service. International telephony wasn't extended to the rest of Britain until the 1930s.

Electrophone table - Connected Earth artefact, now at the Museum of London

Electrophone table (1905) : a shared experience

Long before broadcast radio was introduced the electrophone was a clever way for people to listen to live opera, theatre and church services down a telephone line. Transmitters in the venues were routed through the Electrophone exchange and on to subscribers, listening to the requested performance by means of headphones.

The Electrophone company also provided these listening posts for rental in public areas, which meant that customers didn't need a telephone at home to be able to enjoy the entertainment.

So this sort of table might also have been found in a gentlemen's club or salon. The multi-headset tables made it more enjoyable because you could listen and laugh at the same jokes, at the same time, with your friends, which was almost like being there yourself.


The Coherer (circa 1903) : the sensitive heart of the radio

In the early days of wireless development, the coherer was the invisible heart of every radio receiver. It was actually invented by Edouard Branly, but Marconi developed it to be the force behind his successful radio experiments.

The coherer was filled with metal filings that bunched together every time they picked up an electrical radio wave through the aerial. These carried the 'charge' through to a pair of headphones, on which could be heard the telegraph signals.

This is a Marconi pattern coherer, typical of the type used at the turn of the century, when President Roosevelt and King Edward VII exchanged historic radio messages across the Atlantic in 1903.

fun and games

Can you beat our games? Explode equipment to see what's inside, hear the changing sounds of telecommunications, see how telecommunications designs have changed over time or send an e-postacard.

what's on

The UK's first permanent gallery dedicated to the history of information and communication technologies opens in the new Information Age gallery at London’s Science Museum.

audio history

Take a trip down memory lane with extracts of the interviews which have been recorded as part of the Connected Earth oral history programme.

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100 years of automatic switching!
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