Tape Measure Yagi

thingiverse

Hi, these little things slide down a 21.5mm overflow pipe which forms a boom and hold tape measure cut into lengths to create a yagi for amateur radio. I used six sets to build an eleven db gain antenna for 144MHz - the two meter band - for a competition. These are the dimensions I used to make my yagi: https://m0ukd.com/homebrew/antennas/144mhz-2m-portable-yagi-vhf-beam-antenna/ The overflow pipe I used was from B&Q: https://www.diy.com/departments/floplast-overflow-waste-pipe-dia-21-5mm-white/109187_BQ.prd And the tape measure was two of these budget tape measures (twelve mm width): https://www.diy.com/departments/3m-tape-measure/1780202_BQ.prd For a mast adapter see this: https://www.thingiverse.com/thing:2955775 This one part fits all - use the same part for driven element and all directors/reflector. It has a hole for coax to enter into it for driven element... The lid helps to keep things square and straight. This should require no support when printing. The hole in the base is for a six mm neodymium magnet to hold elements folded neatly while transporting. The holes for the lid take three mm self tapping screws, these pass through the mount and grab the boom to stop elements moving/rotating. I would recommend one short screw about a quarter inch and another longer at about three quarters. If you need to strengthen the boom I have found a dowel that fits inside the pipe quite snugly... You can drive one self tapper through the PVC Pipe into the dowel and it won't move again, and is still easy to remove if you want to make the antenna light again.