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By wireless it was probably meant that it was powered by battery, rather than by mains power.
by FreeFull 7y ago
By wireless it was probably meant that it was powered by battery, rather than by mains power.
- buckminster 7y agoI think it's using the old-fashioned terminology. A wireless or wireless radio is just a radio.
- em-bee 7y agoa simple radio receiver works without a battery. we built those in school. the electricity induced by the radio signal is enough to drive a small speaker.
- roywiggins 7y agoEspecially if you have a transmitter at full volume one room over, you'd be able to pick that up loud and clear on a crystal radio. I think you could make a small unpowered crystal radio using 1919 tech, since there's no amplification.
- Sharlin 7y agoSuch a device is commonly called a crystal radio[1] and they truly are ridiculously simple. If you don’t need a tuner or an amplifier, which in this case was likely, the only components required to build an AM receiver are an antenna, a diode, and an earphone. The name derives from an early type of diode based on a piece of crystalline mineral, discovered by Braun in 1874[2]. [1] https://en.wikipedia.org/wiki/Crystal_radio https://en.wikipedia.org/wiki/Crystal_radio [2] https://en.wikipedia.org/wiki/Crystal_detector https://en.wikipedia.org/wiki/Crystal_detector