Wired connections

How do you send a message across great distances when technology is still in its infancy? Samuel Morse found the answer with his ingenious code of short and long signals—a breakthrough that laid the foundation for global communication. Just decades later, Alexander Graham Bell transformed everyday life with the telephone, making real-time conversation possible.

Morse Code

The Morse code or Morse code was invented by Samuel Morse (1791–1872). He was actually an artist who made oil paintings. The idea was to be able to quickly transmit text messages over long distances. Each letter of the alphabet had a special code consisting of short and long signals. The signals could be electric telegraph lines, sound signals or light signals with a lamp. The message transmission was initially completely manual. A telegraph operator pressed a telegraph key and created the long and short signals, which were then received by another telegraph operator as, for example, sound signals, and the corresponding letters were written down on paper. A skilled telegraph operator could transmit around 250 letters per minute. Later, telegraphing became more or less automated. The telegraph was first used on electrical lines, between railway stations and cities, later wirelessly to ships at sea or airplanes in the air. The advantage of Morse code is that messages can be transmitted with fairly simple technical tools, even in the presence of significant interference. Morse telegraphy is no longer used except by enthusiasts (for example, radio amateurs), but in disaster situations, where technical devices in society have been knocked out, it can be an important backup (cf. the film "Independence Day").

The Telephone

The telephone is invented by Alexander Graham Bell (1876). Now it is possible to transmit speech over telegraph lines. The telephone quickly becomes very popular, and Stockholm becomes the world's most telephone-dense city in 1890. Telefonaktiebolaget LM Ericsson (now Ericsson) is founded in 1896 in Sweden and becomes a world leader in telephony.

Many interesting phones were produced by Ericsson, especially the one called Ericofon, popularly called Kobratelefon (Cobra), was launched by the company LM Ericsson in 1956 and manufactured until 1982.

The original telephones were for manual connection with switchboard operators. Around 1920, automated connection was introduced. The telephone number was transmitted with a dial as electrical pulses to the telephone exchange. With electronic switches in the 1970s, push-button telephones were introduced, where numbers consisted of tone dialing (DTMF - Dual Tone Multiple-Frequency).