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The helix was wound using an 80 metre length of 24/0.2mm PVC coated wire, on a 3m length of 50mm diameter plastic drainpipe. There are approx. 500 turns wound nominally 5.25 turns per inch on the top half, and 3.5 turns per inch on the lower half. This brought it short of the bottom but the end was just spiraled down to the end of the pipe.

The top hat measures 2ft x 2ft and was cut from half inch bird cage mesh. It is sandwiched between two aluminium plates. With the addition of washers it was bolted through to secure it to a 50mm straight pipe connector. A ring tongue terminal connected to a spade connector via a short length of wire enabled ease of connection to the antenna.