getontheairVerticals — 17 ft whip and 4WAVE
Two different antennas get called “a vertical” at a park. Do not mix the recipes.
A. 4WAVE portable HF (recommended here)
Mast + radiator + 9:1 UNUN + hitch/RV/stealth mount + radials 12 / 17 / 33 ft. Packs under 4 ft. This is the vertical on 4waveantennas.com and the full how-to is 4WAVE.
Use it for tailgate POTA and RV pads. Do not use the hitch mount as a SOTA station.
B. Classic quarter-wave whip
- Hardware: ~17 ft stainless telescoping whip on a ground spike or tripod (roughly a 20 m quarter-wave; other bands need other lengths or a coil).
- Radials: at least 4–8 on the grass. More is better. Zero radials is a dummy load with a view.
- Pattern: low-angle radiation that can be excellent for DX, mediocre for close-in NVIS on 40/80.
- SOTA: keep the whole radial field inside the 25 m AZ. A pretty takeoff that spills down the wrong slope can put the far radial outside the zone.
Shared rules (both)
- Low-angle is the point. If you need Ohio on 40 m from western PA, hang a wire low instead.
- Counterpoise is half the antenna. Vehicle chassis is not a radial field.
- If you cannot lay radials (boardwalk, snow, angry rangers), use an EFHW.
Length cheat (quarter-wave, feet ≈ 234 / fMHz)
| Band | Approx. ¼-wave |
|---|---|
| 10 m | ~8.2 ft |
| 12 m | ~9.4 ft |
| 15 m | ~11 ft |
| 17 m | ~13 ft |
| 20 m | ~16.5 ft |
| 40 m | ~33 ft (coil or a different antenna) |
A 17 ft tourist whip on 40 m without a coil is not a 40 m antenna. 4WAVE + 9:1 + tuner is a different compromise — see that page.
Radials are the other half
A quarter-wave vertical is a monopole. The missing quarter-wave is the radial field. Four radials on the grass is a start; eight is better; sixteen is a Field Day luxury. Equal lengths are tidy; mixed lengths (as on the 4WAVE 12/17/33 kit) still work and spread resonances.
Lay them on the grass. Do not bury them for a two-hour POTA. Do not skip them because the hitch or the tripod is “grounded.” Vehicle sheet metal is a random counterpoise — sometimes it radiates, sometimes it is a dummy load with a license plate.
Keep every radial inside the park / SOTA AZ. Flag the far ends. A radial across a travel lane is how you meet a minivan the hard way.
Elevated radials (a few feet up) can work with fewer wires. They also clothesline people. Flag or don’t bother.
Deploying a 17 ft whip (not 4WAVE)
- Spike or tripod on soil you are allowed to use. Boardwalk and frozen crust are a no — use an EFHW on a mast.
- Whip vertical before you extend the last sections. A leaning 17 ft stick is a spear.
- Radials out, 90° or better spacing if you only have four.
- Coax dressed; 1:1 choke at the feed if RF shows up on the radio.
- Low-power SWR on 20 m first (that is what 17 ft is). Other bands need a coil, a tuner, or a different length.
- Then operating power.
A coil-loaded 40 m “tourist” whip is a different antenna. It will not match the 20 m table above. Measure.
Pattern and when to hang a wire instead
Low-angle radiation is why people fuss with verticals: skip on 20–10 m from a parking lot. High-angle / NVIS on 40 m (Ohio from western PA on a summer afternoon) is not this antenna’s job. Hang a low EFHW for close-in 40. Use 4WAVE when the truck is the mast and you want the 9:1 + specified radials without cutting a 17 ft whip per band.
SOTA: the whole radial field in the 25 m AZ. A pretty takeoff down the wrong slope that puts a radial outside the zone is how activations get rejected.
Common-mode on a vertical
The coax shield will try to become another radial. A choke at the feed forces current into the wires you laid. If you skip the choke and skip the radials, the radio chassis is the radial — hot mic, USB dropouts, a laptop that locks up. Fix the antenna; do not turn the power up.
Habits / gotchas / checklist
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Notes & edits
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