Tape Measure Yagi by preseli

Last crawled date: 3 years, 1 month ago

Hi, these little things slide down a 21.5mm overflow pipe (which forms a boom) and hold tape measure cut into lengths to make a yagi for amateur radio.
I used 6 sets to make a 11db gain antenna for 144MHz (the 2m 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 2 of these budget tape measures (12mm 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 is a one fit for all... use the same part for driven element and all the directors/reflector. It has a hole for the coax to enter into it for the 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 6mm neodymium magnet to hold the elements folded neatly while transporting.
The holes for the lid take 3mm self tapping screws, these pass through the mount and grab the boom to stop the elements moving/rotating. I would recommend one short screw about 1/4" and another longer at about 3/4"
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