Ultra Portable 2m/70cm Yagi-Uda / Dipole Antenna Parts

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This thing is a collection of parts to build an ultra-portable duo band Yagi-Uda antenna or a dual-band dipole for 2m and 70cm frequencies. The Yagi-Uda weighs about 340 grams, making it easy to transport in a backpack as its elements can be nested inside the boom. The files contain the upper and lower side of element mounting brackets that clamp onto a 16mm PVC electrical installation pipe. Radiators are made from 2.4mm aluminum welding rods for TIG welding. Coax cable is connected by sticking conductor ends into side holes before tightening down radiating elements' clamp screws. Nuts inside brackets double as connectors. You will need: About 5m of RG58 coax cable 6 M5x30 cylinder head screws 6 5.3/15mm washers 2 5.3/10mm washers 6 M5 hex nuts 6 M5 wing nuts 1 piece of 16mm dia PVC electrical pipe (about 60cm long) 1 piece of PP-cord for attaching the cap to the boom 1 coax plug of your choice (PL/N/BNC/etc.) As you see in pictures, I wound 9 turns of coax around the boom after pulling it through a hole and along the length of the rear end, acting as a choke coil. Radiating elements' lengths are as follows: for 70cm frequencies, cut them to 149mm per side; for 2m frequencies, they need to be 486mm per side. Adjust their lengths for minimum VSWR at your desired frequency range by leaving some extra length initially. The reflector elements are as follows: For 70cm frequencies: one piece of 356mm For 2m frequencies: two pieces of 514mm each, or a single piece of 1028mm that can be bridged with a 55mm long rod in the free slot of the bracket. Element distances along the boom are as follows: For 70cm frequencies: 110mm apart For 2m frequencies: 414mm apart You can easily leave out reflecting elements and use one bracket with radiating elements to form an effective but unobtrusive 2m/70cm dipole antenna for your balcony. For a single-dipole setup, cut radiating elements separately for easy length adjustment inside the bracket.