You can find ten thousand blog posts, but only three truly reliable PDFs worth printing and laminating for your workshop:
: Its slim vertical profile meets many "stealth" antenna restrictions and, when built with copper tubing, is extremely weather-resistant. Technical Specifications & Performance Typical Value / Description ~3 dB over a standard 1/4 wave ground plane Frequently achievable at 1.1:1 or 1.2:1 when tuned properly Matched to 50 ohms for standard coaxial cable Radiation Pattern Omnidirectional (Horizontal plane) Common Design Variations The DBJ-1: A VHF-UHF Dual-Band J-Pole - ARRL j-pole antenna design pdf
The dimensions are slightly different because of the plastic dielectric in the ladder line (Velocity factor ~0.82). You can find ten thousand blog posts, but
The J-pole antenna is a vertically polarized, omnidirectional half-wave radiator that uses a quarter-wave stub for impedance matching. It is popular among amateur radio operators for its simplicity, durability, and lack of ground plane requirements. Design & Theory It is popular among amateur radio operators for
You can find ten thousand blog posts, but only three truly reliable PDFs worth printing and laminating for your workshop:
: Its slim vertical profile meets many "stealth" antenna restrictions and, when built with copper tubing, is extremely weather-resistant. Technical Specifications & Performance Typical Value / Description ~3 dB over a standard 1/4 wave ground plane Frequently achievable at 1.1:1 or 1.2:1 when tuned properly Matched to 50 ohms for standard coaxial cable Radiation Pattern Omnidirectional (Horizontal plane) Common Design Variations The DBJ-1: A VHF-UHF Dual-Band J-Pole - ARRL
The dimensions are slightly different because of the plastic dielectric in the ladder line (Velocity factor ~0.82).
The J-pole antenna is a vertically polarized, omnidirectional half-wave radiator that uses a quarter-wave stub for impedance matching. It is popular among amateur radio operators for its simplicity, durability, and lack of ground plane requirements. Design & Theory