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Dead medium: Candle-Powered Radio; Bayliss's Clockwork Radio
From: wex@media.mit.edu (Alan Wexelblat), sej@aol.com (Stefan Jones)

Candle-Powered Radio

From: wex@media.mit.edu (Alan Wexelblat)
Source(s): excerpt forwarded to me from "Design for the Real World" written by Victor Papanek. I'm not sure this is a dead tech or still in use...

"In 1962 I began to design and develop a new type of communications device.

"An unusually gifted graduating student, George Seegers, did the electronic work and helped build the first prototype. The resulting one-transistor radio, using no batteries or current and designed specifically for the needs of developing countries, consisted of a used tin can. (...) This can contained wax and a wick that burned (just like a wind-protected candle) for about twenty-four hours. The rising heat was converted into enough energy (via thermocouples) to operate an earplug speaker. The radio was, of course, non-directional, receiving any and all stations simultaneously. But in emerging countries, this was then of no importance: there was only *one* broadcast (carried by relay towers placed about fifty miles apart).

"Assuming one person in each village listened to a 'national news broadcast' for five minutes daily, the unit could be used for a year until the original paraffin wax was gone. Then more wax, wood, paper, dried cow dung (which has been successfully used as a heat source for centuries in Asia), or for that matter anything else that burns could continue to keep the unit in service. All the components: earplug, speaker, hand-woven copper radial antena, and 'earth' wire terminating in a (used) nail, tunnel diode, and thermocouple, were packed in the empty third of the can. The entire unit was made for just below 9 cents (1966 dollars).

...

"After further developmental work, the radio was given to the U.N. for use in villages in Indonesia. No one, neither the designer, nor UNESCO, nor any manufacturer, made any profit or percentages out of this device since it was manufactured as a 'cottage industry' product."

The Bayliss Wind-up "Freeplay" Radio

From: sej@aol.com (Stefan Jones)
Source(s): Donald G. McNeil Jr., New York Times News Service, 1996

"MILNERTON, South Africa - Even in relatively rich South Africa, half the homes have no electricity. Go far enough off the beaten track and there are villages with no place to buy even a little AAA battery. So in much of Africa, the portable radio is of little use.

"Maybe not for long. For about six weeks now, a small factory in this town just north of Cape Town has been cranking out radios with cranks. Give the handle a few aerobic turns and the Freeplay radio holds forth for half an hour.

"It is no threat to a Sony Walkman. It weighs six pounds, it's built like an overstuffed lunch box, and it has a tinny speaker. But its wholesale price is only $40 and it gets AM, FM, and shortwave, meaning it can pick up the British Broadcasting Corporation or the Voice of America, so a circle of mud huts can zip back into the Information Age with a twist of the wrist.

"There is a market out there. 'Ghana wants 30,000,' said Christopher Staines, an executive of BayGen Power, the manufacturer.

"Their next product, due out next year, is a wind-up flashlight.

"The manufacturer, BayGen Power, is just as offbeat as its wares. The $1.5 million in venture capital that founded the company came from British foreign aid; the Liberty Life Foundation, the philanthropic arm of a major South African insurance company, and the socially- conscious owners of the Body Shop, a British cosmetics chain. A third of the company's factory workers are blind, deaf, in wheelchairs, or mentally ill, and a consortium of agencies for the disabled owns 60 percent of the company's stock - one of Liberty Life's conditions.

"The patent is the work of Trevor Bayliss, a British scientist who in 1990 was listening to a BBC program on AIDS in Africa that mentioned the difficulty of sending the safe-sex message because many villages could not afford batteries. He went to his workshop, built a prototype, and then could not market it.

"There are actually 13 patents covering the mainspring and gears that drive a little dynamo. The spring does not in any way resemble a Swiss watch's. Unwound, it is 30 feet long and designed for rewinding auto seat belts. A double-spool mechanism keeps its tension constant, which is crucial, and the gearing is sophisticated."

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