Sunday, May 6, 2018

Building a 7 EL 220 mhz Yagi from the Scrap Pile...

Another of the antenna that was destroyed in the tower crash was my 11 element 220 mhz yagi... It was originally installed with vertical polarization, as I used it mostly for FM simplex with some friends about 30 miles away, and for some of the local repeaters. It was really torn up... a section of the boom and 4 elements were crunched up and broken so badly, there was no hope for that part of the antenna.

I decided, rather than spend $$ to put it back like it was, to salvage when I could and build a 7 element version from the wreckage. That should be more than adequate for my 220 mhz FM needs without spending any money for materials or hardware.By salvaging the materials and hardware from the scrap pile, this yagi cost my $0...my kinda price!

 This was all of the materials and usable parts left from the once 11 Element Long Boom Yagi...

 I disassembled the antenna, straightened the boom and element sections in my redneck tubing straightener (see previous blogs about that), and began measuring the boom for the proper element locations (based on info I found on the web for a 7 element 220 mhz yagi).

 The boom was reassembled, and redrilled for proper element placement. Once reassembled, I had to find a new balance point for the boom-to-mast clamp.

 The antenna was clamped to my test tower section for tuneup. It's installed upside down in this pic (matching rod down, should be above the boom)...

 The antenna tuned up OK, and it ready for installation on the primary tower...

Another look down the boom from the front of the antenna. All finished and ready to go!


Dave WB4IUY