Homebrewing a Slim Jim Antenna

Slim Jim antenna, as the name implies, has a very slim design and hence very little wind loading. JIM stands for "J Integrated Matching" as it uses a J type matching stub. Slim Jim antenna was described by Fred Judd, G2BCX in 1978. The antenna has a lower takeoff angle and hence reported to have better performance than 5/8 wavelength ground plane antenna. People have made it using half inch copper pipe, ladder line and many other options! Approximate gain in the horizontal plane has been mentioned as around 2 dBi. Read More: johnsonstechwo...