Table of Contents
Can a radio work without battery?
Crystal radio receivers are a very simple kind of batteryless radio receiver. They do not need a battery or power source, except for the power that they receive from radio waves using their long outdoor wire antenna. The temperature differential generated enough current to operate the low-drain receiver.
What kind of diode do I need for a crystal radio?
The 1N34A germanium diode is the modern substitute for galena and most other germanium small-signal diodes will also work well. Silicon diodes are not a good choice because their much higher barrier potential requires larger signals for efficient rectification.
Why is it called a crystal radio?
A crystal radio receiver, also called a crystal set, is a simple radio receiver, popular in the early days of radio. It is named for its most important component, a crystal detector, originally made from a piece of crystalline mineral such as galena. This component is now called a diode.
Do crystal radios still work?
They are still sold as educational devices, and there are groups of enthusiasts devoted to their construction. Crystal radios receive amplitude modulated (AM) signals, although FM designs have been built. They can be designed to receive almost any radio frequency band, but most receive the AM broadcast band.
Who invented crystal radio?
Oleg Losev
Crystal radio/Inventors
Are crystal radios AM or FM?
Crystal radios receive amplitude modulated (AM) signals, although FM designs have been built. They can be designed to receive almost any radio frequency band, but most receive the AM broadcast band. A few receive shortwave bands, but strong signals are required.
What is a cat’s whisker Set Radio?
A crystal radio that uses a real crystal is called a “cat’s whisker” set, because of the way that the wire dangles over the crystal. Essentially, you need to constantly hand-tune them while you’re listening, or else you’ll lose the signal. It’s terrible.
What are some common mistakes when building a crystal radio?
A common mistake when building a crystal radio is to load the tuned circuit excessively. The Q of the tuned circuit must remain high to give selectivity or strong radio stations will all mix together. A good design will usually have low-impedance taps on the inductor for connections to the antenna and diode as shown in the schematic.
What kind of wire do you use for a crystal radio?
Generally you’ll be dealing with two different types when it comes to crystal radios, insulated wire and magnet wire. For all intents and purposes on this project, insulated wire and magnet wire are the same thing. It doesn’t matter which you use, though you can see in the picture below that I used magnet wire.
Why are my crystal radio coils not working?
There are literally 100’s of crystal radio designs. Possibly the resonant frequency of your coils is not in the range of local stations. Possibly some coil is wound incorrectly. Almost all crystal circuits need a high impedance earphone; if you don’t know what that is you probably don’t have one.