The Tape Measure Yagi
Several days ago, I started thinking about building my own antenna. Not an uncommon thing in the realm of amateur radio, of course, but I’d never tried before and my soldering skills were — shall we say — somewhat rusty. Currently, there’s a Diamond X50 antenna in my attic. Generally speaking, it works well and provides a modest amount of gain on both 2m and 70cm. But when it’s connected to an HT that puts out a mere 4W on “high” power, it can make FM simplex work over more than a few miles fairly difficult. I’d also like to work satellites, and an attic-mounted omni isn’t a particularly good choice for that.
So, I decided to build a beam antenna; specifically, a three-element Yagi constructed from an old steel tape measure and some cheap PVC parts. K4TMN has put together an excellent guide to building a tape measure Yagi for 2m, with plenty of photos and a short parts list. It really could not be easier to follow, even for a total novice like myself.
Within an hour, I had a finished antenna, and most of that time was spent triple-checking measurements and fittings. I took it outside, connected it to my HT, and aimed it toward a repeater that’s normally difficult to receive and nearly impossible to hit from my house (with the omni in my attic). With the Yagi just 5 feet off the ground, in my hand, the output was full quieting and I was easily able to get in to the machine. Success! Next, I need to get my hands on an SWR meter to see if it’s as good as folks claim.
I did make two small modifications: I used RG-8X coax, since that’s what I had on-hand; and, I used a 90º elbow and an additional short piece of PVC to make a pistol grip-style handle. Neither are essential by any means.
The tape measure yagi is an excellent first antenna project. It’s easy to build from inexpensive parts—many of which you may already have around the house. It also performs well, especially given the price. For less than $10, I have a truly useful antenna that should serve me for a while to come!