Observed arrival · 2026-10-03
Short Dipole Coil Calculator
A browser calculator estimates the loading-coil turns and build details for shortened dipole antenna legs.
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◎Niche
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ƒJS
- For
- HF antenna builders and amateur-radio operators
- Worth noticing
- It cites Jerry Hall’s 1974 QST equation and Wheeler’s 1928 single-layer coil formula, with insulation dimensions affecting the result.
Field notes
Inputs cover band, leg length, wire gauge and insulation type, and PVC form size, including a custom outside-diameter option. The output compares nearby half-turn counts and reports both coil and winding details; the page advises removing half a turn and checking again if the antenna resonates low. Its dimensions use typical insulation diameters, so a different wire spool may shift the answer.
Observed signals
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
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