w8io

The W8IO Antenna Site - Download Page

(23 July 2015)


My current software (zipped files)


144 MHz long Yagi NEC files

The VHF antennas shown above include the "raw" element lengths.  That is, the element lengths are those used with a wood or plastic (dielectric) boom or supported above or below a metal boom with an large insulator. To convert these raw lengths into actual lengths used when passed through the center of metal booms, you need to add a correction factor, based on whether the element is insulated and passes through the center of a metal boom, or is shorted directly to the metal boom with a clamp. If the element is insulated when it passes through the metal boom, the correction factor is approximately 1/4 the diameter of the boom. For example, for a 36" (raw length) insulated element passed through the center of a 1" metal boom, the correction factor is 0.25", so the actual length should be 36.25" when built.








Comments are welcome!

contact Roger: email to 

rgcox2 (at) gmail.com

Roger Cox - Spring Lake, MI