Radio-controlled model

A radio-controlled model (or RC model) is a model that is steerable with the use of radio control. All types of vehicles imaginable have had RC systems installed in them, including cars, boats, planes, and even helicopters and scale railway locomotives.

Radio control has been around since Nikola Tesla demonstrated a remote control boat in 1898. World War II saw increased development in radio control technology. The Luftwaffe used controllable winged bombs for targeting Allied ships. During the 1930s the Good brothers Bill and Walt pioneered vacuum tube based control units for R/C hobby use. Their "Guff" radio controlled plane is on display at the National Aerospace museum. Ed Lorenze published a design in Model Airplane News that was built by many hobbyists. Later, after WW2, in the late 1940s to mid 1950 many other R/C designs emerged and some were sold commercially, Berkeley's Super Aerotrol, was one such example.

Originally simple 'on-off' systems, these evolved to use complex systems of relays to control a rubber powered escapement's speed and direction. In another more sophisticated version developed by the Good brothers called TTPW, information was encoded by varying the signal's mark/space ratio (pulse proportional). Commercial versions of these systems quickly became available. The tuned reed system brought new sophistication, using metal reeds to resonate with the transmitted signal and operate one of a number of different relays. In the 1960s the availability of transistor-based equipment led to the rapid development of fully proportional servo-based "digital proportional" systems, achieved initially with discrete components, again driven largely by amateurs but resulting in commercial products. In the 1970s, integrated circuits made the electronics small, light and cheap enough for the 1960s-established multi-channel digital proportional systems to become much more widely available.

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