Hand Crank Radio

Lore & Background

The modern clockwork radio was designed and patented in 1991 by British inventor Trevor Baylis as a response to the HIV/AIDS crisis. He envisioned it as a radio for use by poor people in developing countries, especially in Africa, without access to batteries. In 1994, British accountant Chris Staines and his South African partner, Rory Stear, secured the worldwide license to the invention and cofounded Baygen Power Industries (now Freeplay Energy Ltd), which produced the first commercial model. The key to its design, which is no longer in use, was the use of a constant-velocity spring to store the potential energy. After Baylis lost control of his invention when Baygen became Freeplay, the Freeplay Energy units switched to disposable batteries charged by cheaper hand-crank generators. Like other self-powered equipment, windup radios were intended for camping, emergencies and for areas where there is no electrical grid and replacement batteries are hard to obtain, such as in developing countries or remote settlements. They are also useful where a radio is not used on a regular basis and batteries would deteriorate, such as at a vacation house or cabin.

In Their Own Story

During World War II, U.S. troops sometimes employed hand crank generators, GN-35 and GN-45, to power Signal Corps Radio transmitter/receivers. The hand cranking was laborious, but generated sufficient current for smaller radio sets, such as the SCR-131, SCR-161, SCR-171, SCR-284, and SCR-694. The World War II-era Gibson girl survival radio used a hand-cranked generator to provide power; this avoided the unreliable performance of dry-cell batteries that might be stored for months before they were needed, although it had the drawback that the survivor had to be fit enough to turn the crank. Survival radios were invented and deployed by both sides during the war. The SCR-578 (and the similar post-war AN/CRT-3) survival radio transmitters carried by aircraft on over-water operations were given the nickname "Gibson Girl" because of their "hourglass" shape, which allowed them to be held stationary between the legs while the generator handle was turned.

Reader's Guide

The Hand Crank Radio is a human-powered device useful as emergency equipment, when natural disaster, war, or civil disturbance make regular power supplies unavailable. It has also been seen as economical for use in poor countries, where batteries may be expensive and mains electricity unreliable or unavailable. It is also an environmentally preferable alternative to the use of disposable batteries, which are a wasteful source of energy and may introduce heavy metals into the environment. Communication is a common application for the relatively small amount of electric power that can be generated by a human turning a generator. Windup radios designed for emergency use often include flashlights, blinking emergency lights, and emergency sirens. They also may include multiple alternate power sources, such as disposable or rechargeable batteries, cigarette lighter receptacles, and solar cells.

Did You Know?

• The modern clockwork radio was designed and patented in 1991 by British inventor Trevor Baylis as a response to the HIV/AIDS crisis.
• During World War II, the Gibson girl survival radio used a hand-cranked generator to avoid unreliable dry-cell batteries.
• The key to the original Baygen design was a constant-velocity spring to store potential energy, though this design is no longer in use.
• Windup radios are useful where a radio is not used regularly and batteries would deteriorate, such as at a vacation house or cabin.
• The pedal radio, developed by Alfred Traeger in 1929, was a radio transmitter-receiver powered by a pedal-driven generator for remote Australian outback homesteads.