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====== Creating a Yagi Antenna ======

===== Parts Needed =====

  * (2) 2x4x8'
  * (~16) metal coat hangars
  * Matching transformer (like [[https://www.walmart.com/ip/RCA-VH54-LVH54N-Indoor-Matching-Transformer/20588615?wmlspartner=wlpa&selectedSellerId=1131&adid=22222222227014895810&wl0=&wl1=g&wl2=c&wl3=40874917352&wl4=pla-78766514312&wl5=9017517&wl6=&wl7=&wl8=&wl9=pla&wl10=112562428&wl11=online&wl12=20588615&wl13=&veh=sem|this one]] for example)
  * (6) small washers

===== Tools Needed =====

  * miter saw to cut 2x4's to length
  * strong wire cutters to cut metal coat hangars
  * pliers to straighten wire cutters
  * screwdriver and a few wood screws
  * stapler and ~30 staples
  * coax crimper and wire end
  * small piece of sandpaper

===== Procedure =====

  - Go to [[https://www.antennaweb.org/Address]] to map out direction and distance to towers.
  - Decide on a target RF channel (for Zeeland I used RF channel 8 for 3.1 CBS because that was the most difficult to pick up).
  - Figure out the frequency associated with that RF channel (e.g. [[http://otadtv.com/frequency/index.html]]). I used 183.
  - Measure available space and verify availability of a coax cable to connect.
  - Go to [[https://www.changpuak.ch/electronics/yagi_uda_antenna_DL6WU.php]].
    - Enter your target frequency.
    - Change "Diameter of parasitic Elements [mm]" to 3.
    - Increase the number of elements until you reach the desired boom length. 11 elements will probably be close to a 14' boom length. Make sure that the reflector length isn't longer than your longest coat hangar.
  - Cut all coat hangars to size (one for each director element, one with a gap for the dipole, and one long one for the reflector.
  - Affix the boom in position (connect two 2x4's with another connector piece on the bottom if needed).
  - Attach all director elements and the reflector using staples at the distances given by the Yagi design details.
  - Attach the dipole and matching transformer with two small screws and washers (one washer under the dipole, one above, and one above the transformer, for example).
  - Attach matching transformer to coax.