---
title: "History of telecommunication"
chunk: 3/5
source: "https://en.wikipedia.org/wiki/History_of_telecommunication"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:00:29.329747+00:00"
instance: "kb-cron"
---

Over several years starting in 1894, the Italian inventor Guglielmo Marconi worked on adapting the newly discovered phenomenon of radio waves to telecommunication, building the first wireless telegraphy system using them. In December 1901, he established wireless communication between St. John's, Newfoundland and Poldhu, Cornwall (England), earning him a Nobel Prize in Physics (which he shared with Karl Braun) in 1909. In 1900, Reginald Fessenden was able to wirelessly transmit a human voice.
Millimetre wave communication was first investigated by Bengali physicist Jagadish Chandra Bose during 1894–1896, when he reached an extremely high frequency of up to 60 GHz in his experiments. He also introduced the use of semiconductor junctions to detect radio waves, when he patented the radio crystal detector in 1901.
In 1924, Japanese engineer Kenjiro Takayanagi began a research program on electronic television. In 1925, he demonstrated a  cathode-ray tube (CRT) television with thermal electron emission. In 1926, he demonstrated a CRT television with 40-line resolution, the first working example of a fully electronic television receiver. In 1927, he increased the television resolution to 100 lines, which was unrivaled until 1931. In 1928, he was the first to transmit human faces in half-tones on television, influencing the later work of Vladimir K. Zworykin.
On March 25, 1925, Scottish inventor John Logie Baird publicly demonstrated the transmission of moving silhouette pictures at the London department store Selfridge's. Baird's system relied upon the fast-rotating Nipkow disk, and thus it became known as the mechanical television. In October 1925, Baird was successful in obtaining moving pictures with halftone shades, which were by most accounts the first true television pictures. This led to a public demonstration of the improved device on 26 January 1926 again at Selfridges. His invention formed the basis of semi-experimental broadcasts done by the British Broadcasting Corporation beginning September 30, 1929.
For most of the twentieth century televisions used the cathode-ray tube (CRT) invented by Karl Braun. Such a television was produced by Philo Farnsworth, who demonstrated crude silhouette images to his family in Idaho on September 7, 1927. Farnsworth's device would compete with the concurrent work of Kalman Tihanyi and Vladimir Zworykin. Though the execution of the device was not yet what everyone hoped it could be, it earned Farnsworth a small production company. In 1934, he gave the first public demonstration of the television at Philadelphia's Franklin Institute and opened his own broadcasting station. Zworykin's camera, based on Tihanyi's Radioskop, which later would be known as the Iconoscope, had the backing of the influential Radio Corporation of America (RCA). In the United States, court action between Farnsworth and RCA would resolve in Farnsworth's favour. John Logie Baird switched from mechanical television and became a pioneer of colour television using cathode-ray tubes.
After mid-century the spread of coaxial cable and microwave radio relay allowed television networks to spread across even large countries.

== Semiconductor era ==
The modern period of telecommunication history from 1950 onwards is referred to as the semiconductor era, due to the wide adoption of semiconductor devices in telecommunication technology. The development of transistor technology and the semiconductor industry enabled significant advances in telecommunication technology, led to the price of telecommunications services declining significantly, and led to a transition away from state-owned narrowband circuit-switched networks to private broadband packet-switched networks. In turn, this led to a significant increase in the total number of telephone subscribers, reaching nearly 1 billion users worldwide by the end of the 20th century.
The development of metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology, information theory and cellular networking led to the development of affordable mobile communications. There was a rapid growth of the telecommunications industry towards the end of the 20th century, primarily due to the introduction of digital signal processing in wireless communications, driven by the development of low-cost, very large-scale integration (VLSI) RF CMOS (radio-frequency complementary MOS) technology.

=== Videotelephony ===

The development of videotelephony involved the historical development of several technologies which enabled the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.
The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least by AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However, video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.
Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Only in the late 20th century with the advent of powerful video codecs and high-speed broadband did it become a practical technology for regular use. With the rapid improvements and popularity of the Internet, it became widespread through the use of videoconferencing and webcams, which frequently utilize Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.
Practical digital videotelephony was only made possible with advances in video compression, due to the impractically high bandwidth requirements of uncompressed video. To achieve Video Graphics Array (VGA) quality video (480p resolution and 256 colors) with raw uncompressed video, it would require a bandwidth of over 92 Mbps.

=== Satellite ===