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Convert between RF frequency and wavelength in meters and feet. Essential for antenna design and ham radio band planning.
Calculate half-wave dipole and quarter-wave vertical antenna element length from frequency. Includes velocity factor correction for wire type.
Calculate Standing Wave Ratio from forward and reflected power readings. Convert SWR to return loss and reflected power percentage.
Classic LC resonance formula. L in henries, C in farads, f in Hz. For μH and pF: f (MHz) = 1 ÷ (2π × √(L_μH × C_pF × 10⁻¹²))
f = 1 ÷ (2π × √(L × C))At resonance, parallel LC impedance peaks. Q factor = R / XL determines selectivity and impedance magnitude.
Z = Q × XL (theoretical, limited by parasitic R)At resonance, inductive and capacitive reactances cancel. Either reactance value equals the impedance magnitude divided by Q.
XL = XC at resonance; XL = 2πfLUpdated: July 2026
L = 2.5 μH, C = 180 pF → resonance at 7.48 MHz — suitable for 40-meter band filter center frequency.
Verify external LC values don't pull crystal frequency. Load capacitance affects crystal resonance — use manufacturer load spec.
Calculate LC values to transform 50 ohm feed to 200 ohm antenna impedance at 14.2 MHz for L-network matching.
LC tank circuits resonate at a frequency determined by inductance and capacitance values. Enter L in henries and C in farads (or common subunits μH and pF) to calculate resonant frequency, and estimate impedance characteristics at resonance.