Designs, construction guides, and RF tools for amateur radio operators.
SWR matters for transceiver safety (keep it under 1.5:1), but resonance is what makes an antenna work. Real numbers, real examples, and why you should simulate before you build.
How to select coaxial cable for your antenna system based on frequency, loss, power handling, and installation requirements.
A comprehensive guide to selecting and building baluns for antenna feed systems, covering 1:1 and 4:1 designs.
Dipole lengths, quarter-wave verticals, radials, transformer ratios, and SWR — all in one place.
Open Calculators