Have you ever thought that you feel like build your own crystal set(radio) yourself? That is an easy way but you don't know that so.
We begin to show you in this page the way of how to build crystal sets with your hands easily.
Is this a Japanese style? the simplest method. How optimistic, .... no, optimal!
Japanese domain is small, limited! They can not cast the large antenna! So, they have to assemble the circuit like this to put sensitivity above selectivity, inevitably.
The selectivity can be adjusted with the antenna taps on the coil.
Smaller number turned tap produces better selectivity in compensation for decreasing sensitivity.
And, for improvement of the selectivity, this funny formed coil that is called "Rook coil, Basket weave coil", is created.
This is a coil former that will have been wound some magnet wire.
This form that has been put nine slits on the body, is called "Rook", you can find similar ones on ancient castles, or as a chessman.
Wind up magnet wire on the rook, alternately inside, outside, inside, outside....
diameter 8cm = approx. 3 inches
3.5cm = approx. 1 1/3 inch
I have just remembered the most important of all! That former is the core of packing tapes.
A figure that had been wound up magnet wire as a tuning coil. That is a little shapeless but excellent one.
That form( method of winding ) decreases the self-capacitance of the coil that makes obstructions among wound wires.
I think that that improves selectivity of tuning, and that size of the diameter produces better sensitivity.
#24 wire, 50 turns.
Was that little person winding the coil when you were sleeping?
A variable capacitor.... I recommend for you, purchase kind of ready-made articles.
I can not find it because I live in a poor locality that have never been given the electricity! Crystalsets are practical goods.
(You're a fibber...)
So, you have to make it from some few aluminium plates with your hands by yourself, as a figure on the left hand side.
capacity approx. 300pF
Crystal radio uses minerals(e.g. galena, pyrites... under the pretext of "Crystal") to detect audio sounds from radio electric waves.
But it is hard to get crystal minerals, today. Substitute the germanium diode for them.
If only kind of poor sounds are produced, fit some moderate resistor and capacitor across the output terminals.
R = 50 to 500 kilo ohm
C = 0.01 to 0.022 micro farad
A HARMFUL INSECT!!
This is a joint of antenna taps. Select an optional twig(copper wire) with the alligator clip.
You can adjust the turn numbers of the coil as antenna coil or tuning coil.
By the way, that green colored alligator clip go to the Ground.
Assemble all parts you had created, and a crystal set such alike this will have been built, probably.
Where does this Space-Base belong?
This is not a Japanese "Mikoshi" that is a movable little "Shinto" shrine.