Crank Radio

A hand crank radio is a type of radio, which has a built-in dynamo that generates electrical power upon rotation of the crank handle. The dynamo converts rotational mechanical energy into electrical energy to power the radio. It is a device, which follows Faraday’s law of electromagnetism, where an electrical conductor, cutting lines of magnetic flux, generates electricity. The generated electrical power is usually stored within a rechargeable battery, for later or immediate use by the radio circuit. This type of radio is extremely useful in an emergency because it does not require batteries or any other power source. It is very useful in remote places where a suitable power source may not be available, and consequently it is very popular in places such as Canada.

There are many brands of radios available on the market and they have varying functionality. Some radios also have a built-in flash light function, which is also useful in an emergency. Some radios have a USB outlet socket to enable you to recharge your phone. Usually any phone with a USB charger connects to this outlet for charging. An emergency radio often has a weather band (WB) at 162.5 MHz or has a channel for the reception of NOAA transmissions, which provides the listener with the latest government advice and status about weather events.

Multi-band Receiver

Ideally, an emergency radio should have multiple bands, because some bands work better than others in poor weather conditions. For example, shortwave signals usually bounce between the ground and clouds enabling them to travel larger distances. At the risk of sounding like a trekkie, ionising particles and moisture within the air usually has an adverse impact on FM and VHF transmissions. Therefore, it very much depends upon the disaster you are hoping to survive, but I would go for something that has many bands to cover all possibilities.

Power Supply Options

A pocket radio such as this typically has multiple power supply options. Some radios have built-in sealed rechargeable batteries and the dynamo recharges those batteries only. There may also be a battery compartment for using dry cells; however, this is as a separate power source. Just recently, I came across one radio where, if you installed rechargeable batteries in the battery compartment, then those batteries would be recharged as well thus enabling one to increase the power reserve.

Efficiency and Quality

The efficiency of the overall design is very important in these types of radios. If you were to crank the generator for a minute, then how long would the radio remain operational? A good quality generator produces much larger current per rotation, and good quality batteries would store the charge more efficiently with minimal losses. The radio circuit is also important because an efficient circuit may use much less power, and therefore provide a longer operational time.

Cost / eBay

Crank radios are getting cheaper, especially those coming from China. Each year their functionality increases and prices decrease. The best place for the cheapest prices is eBay as they have a huge section on old and new radios.

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