Around 1860, James C. Maxwell developed a system of equations to describe electromagnetic waves theoretically. Heinrich Hertz succeeded in obtaining experimental proof. The first application of these newly discovered waves was radio technology. The foundation for today's information society had been laid.
Experimental setup for the proof of electromagnetic waves in the style of Hertz (c. 1900) by Max Kohl AG (1876 - 1948, ab 1908 AG)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Between 1886 and 1888, Heinrich Hertz proved experimentally that the physical properties of electromagnetic waves are similar to those of light. This laid the foundation for a new understanding of electrodynamics, from which things that are indispensable today, such as radio, television, broadcasting, cell phones, and radar, were developed.
Induction coil of a Marconi radio station (1898) by Marconi's Wireless Telegraph Company Ltd. (1900 - 1963)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
In 1895, Guglielmo Marconi established the first radio link with a spark-gap transmitter.
He was also the first person to use the radio commercially to transmit news.
Braun system-style bottle transmitter (spark-gap transmitter) with receiver (1903) by Telefunken Gesellschaft für drahtlose Telegraphie m.b.H.Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Marconi had no formal education in physics. He developed his transmitters empirically on the basis of experiments.
In the following years, a number of inventors improved the transmitters by incorporating the principles of physics and greatly increased the transmission power.
Radio receiver in the style of the Slaby / Arco system (after 1899) by Allgemeine Elektricitäts-Gesellschaft (AEG) (1887 - 1967)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Quenched-spark transmitter in the style of Max Wien (after 1916) by Dr. Erich F. Huth Gesellschaft für Funkentelegraphie mbH (1908 - 1945)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Max Wien developed the quenched gap in 1906.
The higher number of sparks per second allowed for a greater range.
The higher frequency is easy to distinguish from atmospheric noise.
Quenched-spark or spark-gap transmitters were widely used on ships in the 1910s.
All conceivable effects of physics were also examined for the reception of electromagnetic waves. Most detectors only worked quantitatively. Initially, the crystal detector prevailed, which also allowed amplitude to be determined.
Schloemilch cell (1903) by Gesellschaft für drahtlose Telegraphie m.b.H System Telefunken (1903 - 1923)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Slaby rod for measuring radio frequencies (c. 1903) by Gesellschaft für drahtlose Telegraphie m.b.H System Telefunken (1903 - 1923)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Maritime radio
Ships at sea get lost in the vastness. In the event of an accident, it is essential to get help quickly, as shown by the disaster of the Titanic in 1912. Accordingly, maritime radio was one of the first applications of the new medium and contributed significantly to its development and distribution.
Quenched-spark transmitter G 1400 for submarines (c. 1915) by C. Lorenz AG (1906 - 1958)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
B.P.S.S. 6.6.16 crystal radio receiver (1916) by C. Lorenz AG (1906 - 1958)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Debeg 7520 maritime distress radio buoy (1976 - 1985) by Deutsche Betriebsgesellschaft für drahtlose Telegraphie m.b.H. (DEBEG m.b.H.)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
Small aircraft receivers E 40, E 160, and C 1916 at the aircraft ground receiving station IoA (Inspection of the Aircraft) (1916) by Gesellschaft für drahtlose Telegraphie m.b.H System Telefunken (1903 - 1923)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
The First World War was one of the biggest driving forces behind the development of the radio.
Wired telephone technology was unsuitable for trench warfare and the use of artillery in particular, so emphasis was put on the development of compact radios for trenches, aircraft, and vehicles.
Radio communication
The successful radio transmission of speech and music occurred for the first time in 1906. In arc transmitters, a microphone is connected to the antenna circuit, which carries several kilowatts of power. Several microphones are then connected in parallel. The invention of the amplifier tube made compact receiving and transmitting apparatus with shorter antennas possible.
Telephone amplifier with Lieben tube (c. 1913) by Allgemeine Elektricitäts-Gesellschaft (AEG) (1887 - 1967)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
The invention of the electron tube in 1910, the high-frequency amplifier in 1911, and the feedback principle in 1913 brought about the breakthrough of the radio.
Speech could now be modulated and transmitted with accurate frequency over undampened waves, and amplified after reception.
RT-196 / PRC -6/6 two-way radio (c. 1955)Museum for Communication Nuremberg, Museum Foundation Post and Telecommunication
This type of 2-way radio was used extensively in the Vietnam and Korean Wars, before it spread worldwide.
Due to the shape of this device, it is often referred to as the precursor to the cell phone.
Auf einer Wellenlänge. Die Erfindung des Funks
Eine virtuelle Ausstellung der Museumsstiftung Post und Telekommunikation.
Kuratorin: Dr. Tina Kubot
Alle Objekte aus dem Bestand der Museumsstiftung Post und Telekommunikation.
www.museumsstiftung.de
Quellen:
Trenkle, Fritz: Die deutschen Funknachrichtenanlagen bis 1945, Band 1, Ulm, 1989.
Rein, Hans; Wirtz, Karl: Radiotelegraphisches Praktikum, Berlin, 1922.
Häfner, Ansgar: Heinrich Hertz, Eine Funkgeschichte, Bühl/Baden, 1991.
