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Antenna Quick Select

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Choosing the right antenna for the mission: the decision table that matches antenna to situation.

Antenna Quick Select

The antenna is the highest-leverage field decision. This page is the decision table; the theory lives in Antenna Design.

The decision table

SituationAntennaWhy
Pocket / pocket-carried beaconHelicalShort, survives abuse (see Helical Antenna)
Pack-mounted, open terrainQuarter-wave whipBest all-rounder (see Quarter Wave Antenna)
Hanging from a pole / treeDipoleNo ground plane needed (see Half Wave Dipole)
Fixed deployment, metal caseQuarter-wave on the caseThe case is the ground plane
Maximum range, staticTall whip or dipole, highHeight beats gain (see Antenna Height Matters)

The two rules

  1. The antenna must match the band: 433 MHz whips are about 17 cm; anything shorter is loaded (see Antenna Lengths).
  2. The antenna must match the mount: SMA standard, not RP-SMA (see Antenna Cable and Connectors).

The field-swap reality

The SMA mount makes the antenna a field decision (see Antenna Mounting): carry a whip and a helical, and match the mission on the day. The Field Repair Kit carries both.

The verification

Whatever the choice: SWR check (see VSWR Measurement) and a range test (see Outdoor Testing). A perfect decision with a broken antenna is a broken decision.