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70 MHz Big Wheel

By Peter OE5MPL and Rudi OE5VRL

Mechanical dimensions

Not drawn is the fixing point of the female N-connector and the center conductor on upper part of hub. We fixed the antenna with a 50 mm diameter aluminium pipe, which was welded onto the lower hub.

Bill of material

8 pcs bolts M8x20 mm for insulator fixing

12 pcs bolts M8x30 mm for lambda/4 spacers

2 pcs bolts M8x10 mm for matching stub

24 pcs nuts

all stainless steel

6 pcs square aluminium 15x15x1,5 mm

3 pcs aluminium rod 2160x8 mm for the arcs

1 pcs aluminium sheet 120x20x2 mm for matching stub

2 pcs aluminium plates 160x160x8 mm for hub

4 pcs polyamide insulators 40 mm long, 30 mm diameter

6 pcs square aluminium 1065x15x15 mm, 1,5 mm wall thickness for spacers

For further information please contact: oe5mpl or oe5vrl both at

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