You may have seen them: small radios that need neither batteries nor an outlet in order to play music. All you have to do is turn the handle on the side for a minute or two, and you can enjoy all the music you want. Seems almost magical, but it isn t. Here we explain how the crank radios work, where they came from and where they are headed.
How Crank Radios Work
A crank radio functions similarly to normal hand-powered generators. These generators produce power by using a magnet and a coil of conductive wire. By wrapping the coil of wire around the magnet and spinning it, a current of electricity is created. The crank will rotate the wire around the magnet and a regulator will make sure that even if you crank quickly, the circuits aren t fried with too much power. You may think that hand-powered generators aren t used often today, but if you ever drive by a wind farm, you will see this same principle in action with the large windmills.
The History of Crank Radios
Hand-powered generators have been around since the 1960s for military applications. However it was in 1831 that Michael Faraday discovered the ability to collect the power using a conductive wire in a magnetic field. He had been working with magnets and motion for years before he discovered the principle of electromagnetic induction. It is also Faraday who created the generator which later led to the modern electric motor and transformer. He also proved that electricity induced from a magnet, electricity from a battery and static electricity are all the same.
All of Faraday s work laid the groundwork for a fellow by the name of Trevor Baylis. This man invented the wind-up radio in 1989 by using a transistor radio, electric motor from a toy car, and a clockwork mechanism from a music box. The crank wound up the spring and released slowly, powering the radio as it did. The crank radios now contain generators that have the ability to store the extra energy. Baylis first came up with the idea after hearing a television broadcast about the underprivileged in Africa. The broadcast explained that if communication could be improved, it would help slow the speed of AIDS. Before the broadcast was even finished, Baylis had a working prototype of the crank radio. This radio was ideal for the conditions he'd heard described for those with little money and no electricity to use. However, the idea didn t catch on until 1994 when his prototype was shown on a BBC TV program. With people backing his work and new partners, Baylis founded a company to begin production on the wind-up radios. The company, Freeplay, is still in business today, and for every crank radio purchased it sends one to Africa.
Where Crank Radios are Going
Few crank radios today consist only of radios that are powered only by cranking. Many of these crank radios, including the Et n Scorpion, EyeMax WB 2009 and Kaito KA888, come with other power source options, including USB, DC jack and even solar panels. By combining all of these options together, you get a product that is useful in a variety of situations. The crank radios were first designed to be sent to Africa, but now they are readily seen in a camper s backpack or an emergency preparedness kit. You can purchase one, put it in your emergency preparedness kit and not have to worry about batteries deteriorating over time. The manufacturers are continually developing new products which can be used in a multitude of situations. This kind of technology will stick around for a long time.