Fisico russo, nasce nel 1859 e si laurea nel 1882 con una tesi sulla dinamo e sugli elettromagneti. Proseguendo le ricerche di Herz a proposito della produzione di onde si convince della possibilità di per la realizzazione di un sistema di comunicazione senza fili. Nel corso delle sue sperimentazioni sviluppa generatori di alta frequenza a scintilla estremamente efficienti. Dopo i primi esperimenti, in cui si raggiungono distanze di una sessantina di metri, aggiunge un’importantissima innovazione. Applicando al ricevitore un filo verticale, una prima rudimentale antenna.
Nel 1895 rende pubbliche le sue scoperte dandone notizia alla Società russa di fisica e chimica. Nel 1897, durante alcune prove di comunicazione tra mezzi navali, raggiunge una distanza di cinque chilometri. Nel 1901 brevetta un sistema per l’ascolto in cuffia dei segnali radiotelegrafici. Durante le sue ricerche si rende conto che i ricevitori per radioonde sono in grado di rilevare fulmini caduti anche a grande distanza, questa scoperta gli da l’impulso, negli ultimi anni della sua vita, a tentare di sviluppare un sistema di previsioni meteorologiche per i mezzi in navigazione. Popov muore a Pietroburgo nel 1906.
Alexander Stepanovich Popov was born on 4th (16th in old calendar) March 1859 in the Ural village Turyinskiye Rudniki of Verkhoturskiy Uyesd in Permskaya Gubernya.
Alexander had six other siblings through his father’s family. His father was a priest. They lived quite modestly. At the age of ten Alexander Popov was sent to the Dalmatovskoye Uchilische priesthood. There he studied from 1869 until 1871. In 1871 Alexander Popov moved to another priesthood: Yekaterinburgskoye Dukhovnoye Uchilische.
In 1873 he moved again, this time to the Perm theological seminary. After finishing his general education classes, he graduated in 1877 and successfully passed exams to enter the Physics and Maths faculty in Peterburgskiy University. Years of study in the University did not go easily for Popov. Being short of money he had to work in his free time as an electrician in a place called ‘Electrotechnology’. During these years his scientific views took their final shape: he was particularly attracted to new physics and electro-technological problems.
Having successfully graduated in 1882 he was invited to stay and prepare to become a professor in the Physics faculty. In 1882 Popov successfully defended his thesis entitled ‘On the principles of direct current magneto and dynamo electric machines’.
In 1901 A.S. Popov became professor of Physics at the Imperior Alexander III Electrotechnical Institute. He was also an honorary Electrical Engineer (1899) and an honorary member of the Russian Technical Society (1901).
Popov’s device arose out of special equipment he made back in 1889 to demonstrate Hertz’s experiments to his students. He used the Hertz vibrator as a transmitter. At the beginning of 1895 he became interested in Lodge’s experiments. (Lodge perfected the coherer and built a radio receiver based on it, through which, in 1894, he managed to receive radio signals at a distance of 40 meters). Popov tried to replicate them, having built his own modified version of Lodge’s receiver.
The main difference between Popov’s receiver and Lodge’s was the following: the Branly-Lodge coherer was a glass tube filled with metal filings, which were able to suddenly change their resistance hundreds of times under the influence of a radio signal. To return the coherer to its initial state to detect a new wave, one had to shake it to re-settle the filings. To this end, Lodge used to insert an automatic drum into his glass tube, which was designed to constantly ‘hit’ the tube. Popov added automatic feedback to the design: the radio signal switched on a relay, which would itself start a bell. The drum would then begin simultaneously hitting the glass tube with filings inside. In his experiments, Popov used a grounded outboard aerial, invented by Tesla in 1893.
On 25th April (7th May new calendar) 1895, at a meeting of the Russian Physics-Chemistry Society in Peterburg University, Popov introduced his invention for the first time. The topic of his lecture was ‘On the effect of metallic powders on alternating current’. In his published description of his device, Popov noted its usefulness for lectures as well as for registering atmospheric perturbations. He also demonstrated his hope that his ‘device would, in the future, with further improvement, be applied to the actual receiving of signals from a distance with the aid of high rate alternating current (as soon as it became possible to generate such high rate alternating current)’. Later, from 1945 on, this event would be celebrated in the USSR as ‘Radio Day’. Working in a marine institution meant limitations for publishing the results of his research. That is why, in keeping with the oath of secrecy he took, he never published new results of his work.
The Central Museum of Communications, named after A.S. Popov, is one of the oldest scientific-technical museums. It is located in the center of St. Petersburg, not far from Isaakiyevskaya Square. The Museum’s unique collection is dedicated to the history and development of different means of communications in Russia and has more than 8 million exhibits in store.