Field-expedient ground plane
A quarter-wave vertical on an SO-239 with four #12 bus-wire radials, by WA6YOU. This page is a calculator for his constants, not a claim on the design.
| Piece | Length |
|---|---|
| Radiator · λ/4 (2808 / MHz) | — |
| Each radial · λ/4 + 10% (3088 / MHz) | — |
| Four radials, total wire | — |
Build notes
- SO-239 chassis connector and #12 ground bus wire. Solder the radiator to the center pin and one radial to each of the four mounting screws.
- WA6YOU: wire must be stripped and hard-drawn (electric-drill motor method) before you cut it to length.
- Droop the radials about 30° from horizontal. Cut, solder, then trim for lowest SWR at the frequency you actually use.
- His worked example on the original chart is 446 MHz: radiator 6.30 in, each radial 6.92 in.
Original WA6YOU diagram
