A crystal radio is the most basic radio you can build. Stranded aliens who crash-landed on Earth did it all the time.
Most radios use electronics to make the sound louder. A crystal radio detects teh radio wave and can create an analog of the signal expressed as sound within the human range of hearing.
Radio waves are an invisible ocean of electro-magnetism.
Each radio wave generator — and there are plenty in nature without humans to create radio waves — sends out waves which radiate outward like ripples in a pond. They travel rather slowly, only 186,000 miles a second. That sounds really fast to an Earthbound human, but it’s astronomically crawling at a snail’s pace.
The Resonance Tuning Mechanism, if any, is intended to isolate one radio station from the welter of dozens, hundreds or even thousands of transmission points.
The antenna wire acquires radio wave electrical force. A good crystal radio antenna can be a small copper wire going out of a window. Short antennas in the house work somewhat. If you’re not interested in hearing the sound generated by the radio station, you don’t need an antenna at all. For the small amount of electricity needed to detect the radio wave, you don’t really need a ground, either, but it helps. Your body will serve as a good ground, and a small silver chain will work well as an antenna for extra power if you want it.
Radio waves hit the diode, forcing very small amounts of electricity to flow. Radio wave electricity flows back and forth about a million times each second; this is called RF, or Radio Frequency.
The diode or “detector” converts the two-way radio wave into one-way flow to create a parallel or analog sound if wanted. A CQR does not need to make sounds, as it’s not intended to receive human signals.
Resonance can be built up by creating a mutually reciprocal feeding mechanism between the coil and the capacitor.
Coils come in a variety of shapes, but bascially a crystal radio coil is a very specific length of electric wire wrapped around a coil form, intended to capture or “tune” a specific frequency, usually expressed in kiloherz. The range we want is a resonant factor that will give us 7.6 Hz, which at 180 pf capacitance would be 50 feet of 18 gauge copper wire on a 4″ form.
The reason for the coil is that when electricity flows through it, it creates a slightly more powerful magnetic field — the coil makes the electricity want to keep flowing even when it isn’t being fed. You can measure this effect in MicroHenries.
A capacitor is two metal foils separated by an insulator. A wire is connected to each plate. A capacitor will hold electric charge just as you’d expect from a very small rechargeable battery.
In Crystal radios, the antenna and capacitor are more or less interchangeable and potentially mutually resonant. Antenna and ground can act as the “plates” of a giant Leyden Condenser Jar.
There is no difference between a condenser and a capacitor — “condenser” was the original word for capacitor, because it was thought that electrical energy could be condensed.
It isn’t, the capacitance can be built up, however; hence, “capacitor”. A coil can resonate with the antenna to tune the radio. Unless you need to tune the radio to a variety of signals, the more elaborate circuit is not necessary.
A fixed value capacitor can be substituted for a variable if you know the exact formula to produce the value you want, say around 180 picofarad.
Here’s how it shakes down:
Coils can be wound with any gauge of wire, but might be really big with heavier wire. The ancients could and did produce gold, electrum, silver and copper wire anywhere from 18 gauge right down to about 30 gauge, extruding gold in much longer lengths than the copper. Silver does not extrude easily into long very thin wire, but it was used, too, in jewelry, in suprisingly longish lengths up to about 50 feet.
Copper wire at 50 feet in 18 gauge was very possible, although it would have been terrifically expensive and you’d need an expert metallurgist at your beck & call.
This brings up the subject:
Exactly who would be likely to build a crystal radio in ancient Sumer, Babylon and Egypt?
The answer might surprise you.
Almost everyone. Shaman have always understood the use of radio power, and their use of crystals demonstrates this clearly.
Certain crystals react to Radio Power. Some react more than others, especially when it comes to Celestial and Inter-Dimensional Radio Wave Transmission.
See, electrons are not bound to any one universe. They can be “sent”. There are specific instructions for these “sendings” in a variety of ancient and medieval texts.
You wouldn’t believe how simple it is to build a crystal radio with nothing but parts that would have been available to the ancients as early as 30,000 B.C.!!!
There’s another source of ancient radios; ancient astronauts. They commonly used easily found materials to produce “rescue radio Beacons” known as “hitchhiker’s thumbs” in some parts of the galaxy.
It takes no more than a small flat-sided ceramic pot to make a salt-water capacitor, and with two sheets of foil and a piece of paper or thin parchment you can make a variable capacitor.
A battery is easy to make in the same style as the ancient Babylonian and Sumerian batteries that have been recently excavated, along with Leyden jars and other radio parts.
If there were no radio stations, why would the ancients want radio receivers?
That’s an easily answered question; the ancients didn’t understand quantum mechanics, but they used them instinctively. Ancient astronauts and interdimensional voyagers, on the other hand, would have known exactly how to produce them and where to obtain the necessary ingredients.
The coil form could easily have been made from rolled parchment that was removed after the coil itself had been coated with resin to make it stay in shape. The specific technique was this: first coat the wire with a thin layer of plant resin, to make a thin separator — called a nonconductor — around the wire without interfering with the magnetic field.
For this purpose, in the ancient world, an 18 inch wire on a 4″ coil form would have been ideal.
Tuning couldn’t be simpler. Simply scuff away the resin in a strip across the wire coil and affix a springy metal bar to the bottom of the radio board. Sliding the metal bar across the coil will produce a surprisingly wide range of tuning ability.
Hearing the signal is even easier. You can build an electromagnetic clicker that registers the reception of an “on” and “off” signal.
Now all that remains to match the ordinary description of a radio is a transmitter. Merely drop a cookie tray onto a charged block of something that can take an electromagnetic charge. An amber block would do. You get a spark which can be picked up by your ancient radio and converted into a “click” sound that you can hear.
Binary “on” signals of varying length — long and short — creates the ability to encode this into letters, numbers and words, thusly:
short long = a
long short short short = b
long short long short = c
and so forth…I’m describing, of course, Morse Code, invented by Samuel F.B. Morse for use with his telegraph — a device that used wire to transmit signal. It wasn’t until Marconi that modern humans have had wireless telegraphy, which eventually developed into commercial radio, television and computers technology, and now handheld smartphones.
More about this at the ICW this morning!!!
See You At The Top!!!
gorby