Enter new values on the lines with the light brown background. Press the carraige-return key within one of these fields to calculate the parameters on the lines with the blue background. This calculator is for when you have in mind the size and pitch of the "square" coil you want and the frequency range you want to cover with it. It then calculates the coil's inductance, maximum and minimum capacity required to tune the range you want, plus the number of turns for the coil and the total length of wire required. You need to allow extra wire for connecting leads.
The formulae used by the calculator are:
Coil Radius | R | = D/2 |
Coil Inductance | L | = R³/(184000*P²) |
Minimum Capacitance | C_{min} | = 1/(4π²(F_{max})²C) |
Maximum Capacitance | C_{max} | = 1/(4π²(F_{min})²C) |
Coil Winding | N | = √(736000L/R) turns |
Wire Required | W | = N√((πD)²+P²) |