One of the most talked about technologies, Radio Frequency Identification (RFID), uses tiny passive electronic tags to track goods through the supply chain. Although RFID has found many uses in the modern age, the concept was originally designed by Russian inventor Léon Theremin as an espionage device.

Source: Wikipedia

Born in 1896, Theremin was a prolific inventor whose devices ranged from electronic musical instruments, such as the Theremin which bears his name, to the concept of interlacing which is still used today for improving the quality of broadcast video signals. From the age of 7 Theremin had developed a fascination with electricity and by 13 was demonstrating advanced optical effects using high frequency circuitry to his peers.

However it is Theremin’s passive listening device nicknamed “The Thing” which will probably prove to be his legacy. Designed as a tiny “bug” for use against American diplomats based in Moscow, “The Thing” relied on electromagnetic energy from an external source in order to transmit audio; the genius behind the idea was that the energy required was not obtained from a battery, but by a remote radio beam at the correct frequency. When activated, The Thing would then retransmit audio back to the sender who could eavesdrop on conversation taking place near to the covert listening device.

“The Thing” was a great success, allowing the Soviets to spy on their American counterparts undetected for seven years due to almost undetectable nature of the passive circuit. In fact the device installed in the Moscow embassy was discovered accidentally when a British radio operator overheard the broadcast from the device.

Despite his work for the Soviet cause, Theremin was interned in a gulag prison camp for several years before joining the KGB where he worked until 1966. He would later work at the Moscow Conservatory of Music where he developed the electronic instrument which still bears his name today. Theremin died in Moscow in 1993 at the age of 97 after a long and varied career.

The passive circuitry used by Theremin went on to form the basis for other similar devices which could be activated and powered remotely by radio waves and formed the inspiration for modern RFID and Near Field Communication (NFC) tags. The future of contactless payments, electronic inventory control and touch travel passes, such as the London Underground Oyster card are all direct descendants of “The Thing”.