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====== QFH Antenna Build ======

{{:antennas:all-around-band-qfh.jpg?400|}}

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 - [[https://www.screwfix.com/p/ced-all-round-band-12mm-x-10m/18298 |Screwfix]] 
  * - M4 Threaded Rods (x4) [[https://www.amazon.co.uk/sourcing-map-Threaded-Thread-Stainless/dp/B0BK52F97W|Amazon]]
  * - M4 Nuts (x24) [[https://www.amazon.co.uk/Nylock-Nylon-Insert-Locking-Stainless/dp/B07VSCG96L|Amazon]]
  * - M4 Washers (x24) [[https://www.amazon.co.uk/25mm-Flat-Washer-Stainless-Steel/dp/B0BVMRXXVF|Amazon]]
  * - Good Quality Coax. (Messi Hyperflex 5 / Ultraflex 7)  [[https://www.hamradio.co.uk/messi-and-paoloni-hyperflex-5-pd-6679|ML&S]]

Whole thing can be built for less than ~£25. Less if you shop around / scavenge a bit more.