A windup radio or clockwork radio is a radio that is powered by human muscle power rather than batteries or the electrical grid. In the most common arrangement, an internal electrical generator is run by a mainspring, which is wound by a hand crank on the case. Turning the crank winds the spring and a full winding will allow several hours of operation. Alternatively, the generator can charge an internal battery.[1]
Like other self-powered equipment, windup radios were intended for camping, emergencies and for use in areas of the world 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.
Windup radios designed for emergency use often included flashlights, blinking emergency lights, and emergency sirens. They also may include multiple alternate power sources such as disposable or rechargeable batteries, auto cigarette lighter plugs, and solar cells.
Contents |
Radios powered by handcranked generators are not new, but their market was previously seen as limited to emergency or military organizations. The modern clockwork radio was designed and patented in 1991 by British inventor Trevor Baylis as a response to the AIDS crisis. He envisioned it as a radio for use by poor people in developing countries 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 PLC), which produced the first commercial model. The key to its design was the use of a constant velocity spring to store the potential energy.