70 MHz Big Wheel
Detailed construction guide for a 70 MHz Big Wheel antenna, including materials and dimensions.
Description
This PDF document details the construction of a 70 MHz Big Wheel antenna, a horizontally polarized omnidirectional array. The design utilizes three full-wave loops, each approximately 2160 mm in diameter, arranged in a triangular configuration. The resource provides mechanical dimensions for the antenna elements and a comprehensive bill of materials, specifying component quantities and types, such as M8 stainless steel bolts, 15x15x1.5 mm square aluminum tubing for spacers, and 8 mm aluminum rod for the arcs. The central hub is constructed from two 160x160x8 mm aluminum plates, with four 40 mm long polyamide insulators supporting the radiating elements.
The feed system incorporates a 50 mm diameter aluminum pipe for mounting and a matching stub constructed from a 120x20x2 mm aluminum sheet, connected via M8x10 mm bolts. The resource includes a diagram illustrating the mechanical dimensions and assembly points, including the N-connector fixing point and the center conductor attachment. The project was published on May 25, 2011, by Peter OE5MPL and Rudi OE5VRL.
DXZone Focus: PDF | 70 MHz Big Wheel | Mechanical Dimensions | 2160 mm loop diameter