You will need
- Wires of various sections, paper, glue, plastic cylinder, knife, scissors
The basis of the coil inductance is a conductor. Around the conductor passing through it a current the magnetic field is always present. The strength of this field depends on the strength of current in the conductor. Another way to strengthen the magnetic field to collapse the conductor into a spiral. This is nothing more than a coil of inductance. The smaller the coil diameter, the more turns the stronger the magnetic field generated by the coil. Hams usually wound these coils on their own.
Inductance is the ability of the coil to create a magnetic field. Inductance is measured in Henry (H).
Coil inductance is not produced in the form of standard parts with standard specifications, as calculated and manufactured for each specific device separately. Therefore, in the manufacture of coil you will need to first consider the characteristics of input and output signals of your radio.
For VHF and short-wave oscillatory circuits are made coils with few turns of thick wire. Some of these coils don't have a frame.
For transmission and reception of radio signals at medium and long wavelengths are used multiturn coil (single-layer and multi-layer). To make the frame for these coils you will need paper or plastic.
The number of turns of the coil when you configure the radios and other equipment will have to pick up experimentally, changing the inductance of the coil. You can do it otmuchivaniem and Domitiana of turns of the coil, but this method is not quite useful in practice. This files most often placed inside the coil pull out a core of special magnetic material. This can be alsever (an alloy of aluminum, iron and silicon).
Magnetic cores concentrate the magnetic field of the coil, thus increase its inductance. With this you can reduce the number of turns of the coil, which leads to the decrease of its sizes and dimensions disturbed.