## Electronics Calculators

Below are some useful links for calculating various values used in electronics.

### Air Core Inductor Calculator

The following is a design tool based on Weaver's formula which calculates the inductance of an air core inductor.

L = (d2 * n2) / (18d + 40l)

where:

L is inductance in micro Henrys,
d is coil diameter in inches,
l is coil length in inches, and
n is number of turns.

d
Coil diameter in inches
l
Coil length in inches
n
Number of turns
L (µH)

### LC Resonance Calculator

The following is a design tool which calculates the resonant frequency of an LC circuit.

f = 1 / (2 π $\sqrt{\mathrm{LC}}$)

where:

L is inductance in Henrys,
C is capacitance in Farads, and
f is resonant frequency in Hertz.

The tool below uses more convenient values. Enter any two parameters and the calculator will present the third parameter for a resonant circuit.

Frequency
MHz
Capacitance
pF
Inductance
nH