antennas:qfh
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QFH Antenna Build
From Scott - 2M0VSR:
https://jcoppens.com/ant/qfh/calc.en.php generates the paper template for the holes.
Quadrifilar helicoidal antenna - Javascript on-line calculator
Compared to solid core wire, it's quite easy to get it into shape, or close enough that it tunes almost smack centre in the band
I think the rods are M4/5/6 threaded rods. Just make sure the rod will go throw the stell banding holes as they are difficult to enlarge.
Think it was this that gave me the original idea: https://tf1ez.com/qfh-antenna-build/
Parts List
- - PVC Pipe (55mm, 1meter or similar)
- - Galvanised Steel Banding - Screwfix
- - Some Good Quality Coax. (Messi Hyperflex 5 / Ultraflex 7 for example)
Whole thing can be built for less than £20 if you shop around / scavenge a bit more.
antennas/qfh.1713299484.txt.gz · Last modified: 2024/04/16 20:31 by 2m0vsr