antennas:qfh
QFH Antenna Build
From Scott - 2M0VSR:
Credits
Inspired by this build: https://tf1ez.com/qfh-antenna-build/
Summary Instructions
The above link has a better guide but the TLDR version is:
- Generate and print the paper templates based on the type of PVC pipe you have. Use: https://jcoppens.com/ant/qfh/calc.en.php
- Tape the cut-outs onto the PVC pipe, making due they are aligned down the pipe.
- Drill out the holes. The centre ones are not strictly needed but you may find it useful to use some wooden dowel rods to support the banding.
- Cut the threaded rods down to size based on the calculator. Leaving them a little long won't do any harm.
- Put the threaded rods though and use a washer/nut against the PVC pipe to hold in place.
- Cut the Banding so that it stretches to the opposite bottom rod. I'd leave a bit extra and trim.
- Use 2 nuts/washers to lock in place the banding on each end.
- Attach the Coax ends to the top of the antenna and run it down the tube. Tie it off to the bottom with some zip ties for strain relief.
Notes:
- You can use low gauge wire as an alternative to banding but it's much more difficult to work with and get aligned well. I used 10mm earth wire for an earlier build and it worked ok.
Parts List
- - PVC Pipe (55mm, 1meter or similar)
- - Galvanised Steel Banding - Screwfix
- - M4 Threaded Rods (x4) Amazon
- - M4 Nuts (x24) Amazon
- - M4 Washers (x24) Amazon
- - Good Quality Coax. (Messi Hyperflex 5 / Ultraflex 7) ML&S
Whole thing can be built for less than ~£25. Less if you shop around / scavenge a bit more.
antennas/qfh.txt · Last modified: 2024/04/24 19:15 by 2m0vsr