A mystery (solved?) on 10 meters, #WATwitter

Back during the flurry of action on 10 meters a few weeks back I noticed the standing wave ratio of my antenna was dangerously high, even after using the autotuner on the K3. I use the Buckmaster OCF dipole for 80-6m and I rarely ever need to tune this particular antenna. I didn’t have much time to fool with it, so I went QRT and didn’t think much about it. I’ve been busy and haven’t had much time for radio anyway.

Fast forward a few weeks and here I am raking leaves over the Thanksgiving break. I decided to wander back into the woods behind my house and check the long leg of the dipole, since I was having some trouble seeing where it was tied off some 90 feet back into the swamp. Sure enough, some sort of natural event had taken place and a 50-60 foot tall tree had fallen near the antenna. One of the branches of the fallen tree had come to rest on the rope supporting the dipole and had pulled everything downwards by several feet.

Using extreme caution to prevent the rather large limb from falling on me, I dragged it off the support rope and watched it crash down with a thud, kicking up swamp water and primordial ooze. The dipole was sagging pretty badly, so I untied the support and re-tied it back at the recommended 8-foot height.

I also noticed a tangle of vines had attacked the dipole like something out of the Day of the Triffids, and the aggressive vines were pulling downwards on the wire. A handsaw and a few satisfying cracks later and the antenna was free and in the clear. Surely that would work out the SWR issues.

Nope. They were as bad as ever, maybe worse. Fortunately, the antenna had a flat SWR on every other band, including 6 meters. 10 remained a mystery.

The next day I had a conversation with my buddy Ronnie, W4RWL, “the Antenna Whisperer,” who immediately suggested that the pressure of the branch on my antenna support rope had caused the wire to stretch and therefore screwed up the important ratio between the lengths of the dipole wires. EXACTLY.

He suggested I shorten the stretched wire a bit. I shall take his advice and employ an antenna analyzer to try and get it back to normal. I will report my results back here when I get around to making the fix. Meanwhile, here’s what the situation looked like when I discovered the fallen tree:

photo 1

Pretty tall tree had fallen behind my home. That branch that’s snapped back was the one that landed on my dipole. I’m not kidding when I say there is swampland behind my QTH!

photo 3

There’s the end of the dipole and the support rope. That nice limb in the foreground is actually on top of the support rope.

#WATwitter

For the second year I managed to participate in the annual Worked All Twitter endeavor. I didn’t do as well as I did last year, owing to a rather busy holiday schedule, but I did get to chat briefly with K5PO and WB0RUR, two of the masterminds behind my favorite ham radio humor column, Ham Hijinks. K5PO, Andy, managed to get a decent net started on 20 meter SSB, and I made the contact with WB0RUR via the net.

Saturday I had a moment, so I went on Twitter and spotted myself calling CQ #WATwitter on 20M PSK31. I had no shortage of contacts, though I think only one or two folks were aware of #WATwitter. I kept the QSOs conversational and scored a new state for the WAS Triple Play with Vermont.

To any readers, I apologize for the paucity of new material over the last few months. As the semester comes to a close I’ll be able to relax from teaching and get back on the airwaves!

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