by Gary Johnson NA6O
Everyone knows how to rotate their Yagi antenna: Just turn the knob and away it goes. But this article isn’t about that rotation, it’s about rotating it a different way, for maintenance. When your beam has a problem wayy out where you can’t reach it, the usual expectation is that the whole thing is going to have to come down off the tower. Many of us have seen balun failures or lost the tip off of an element or had an element twist on the boom, and there’s no obvious or easy way to reach it. It’s bad enough that we have to hire a climber, and even worse when the work involves tramming the whole shebang down to the ground and back up. Thankfully, professional tower busters have tricks that save us much time and effort. The first time you see it, the light goes on and it’s obvious… If only you had thought of if first!
The simplest trick is to rotate the Yagi by loosening the boom in the boom-to-mast clamp, allowing the boom itself to rotate. This lets the elements swing down alongside the tower. Now it’s possible to climb up or down and reach at least the elements that are close to the tower. Our local climber Mark, N9LS, did a service call at my station W6SRR where some plastic clips out on the elements had slipped out of position. He was able to reach them and fix the issue easily.
The more elaborate and flexible trick is to dismount the Yagi entirely while temporarily supporting it at its balance point with some combination of slings, ropes, and a come-along. At N6RO, we had a balun failure on a long 20m Yagi and Hector, AD6D, used this method. Once the antenna is free-floating, it’s easy to position it at any angle along the tower, allowing access to anything that needs attention.
So be sure to consult the pros when you have a problem up the tower. They may even show you a different way to rotate.
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