Friday, October 05, 2007

What goes up, must come down

As they say, what goes up, must come down. Fortunately, sometimes, what goes down sometimes goes back up. I'll explain.

Back in April or May, a pretty nasty storm
came through here. A mature tree (I think it was some variety of oak, but I'm really not sure) got blown down. Fortunately, that tree was at the edge of the woods behind our house and blew over back into the woods, well away from any buildings or cars. Because the ground was very soft at the time, the entire tree blew over, pulling the root system out of the ground, and leaving it just sitting there, with a pretty deep hole where the roots had been before. There was no real rush to do anything about it, but Sharon and I decided that we'd like to get it cut up for cosmetic reasons, as well as allowing the base to fall back into the hole, which kept filling up with just enough water to attract mosquitoes. Sharon called a local tree company and told them what we wanted to have done. Because there were a lot of higher-priority jobs, they told us it might be a little while until they were able to get to the tree.

"A little while" can mean all kinds of different things, and the frame of reference has a lot to do with this. I'll spare you the usual comparisons other than to say that on a geologic scale, it was even less than "a little while" until the tree company came. However, on a conventional day-to-day life scale, I think I'm safe in assuming that waiting from May until October 5 for the tree compa
ny to show up is probably more than "a little while".

As it turns out, there was a good side to them not showing up until today. Another tree, on the edge of the woods, had died at some point in the relatively recent past, and was starting to look like it might decide to come down on its own. Since one of the two main trunks was tilting towards our house, we decided that it'd probably be a good idea to have it taken down professionally, rather than allowing it to fall. Since the guys were already out cutting up the first tree, they gave us a good price to cut down the other tree. (Oh yeah, the other good thing about them not showing up until today was that I decided, pretty much for no reason, that I'd work from home today, so I was at home when they showed up.)

(I don't usually go this long without reference to radio, but I'll bet someone may have figured out
what's coming next). So here's the radio tie-in: One end of my G5RV passed through the branches of the dead tree. I had originally hope to just lower both ends of the antenna enough to get out of the way, but Tom (the foreman) pointed out that since it was still draped through the branches, it would have been destroyed when he started dropping limbs. My big concern was that if I had to drop it all the way down and pull down the support ropes, that I wouldn't be able to get it back up in the air again. (When it was originally put up, a bunch of guys from the local radio club came over, including one with a bow and arrow, who did the trick.) Tom assured me that he'd get it back up in the tree, and since the tree had to come down, meaning the G5RV had to come with it, I really had no choice.

As you can see from the photo, Tom (that's him in the tree) climbed up and cut off a bunch of larger
limbs so there wasn't much left by the time it was time to cut the trunks. He used a pair of climbing spikes, and I figured he'd do the same to get the support rope for the G5RV back up to where it was. It turns out that he had an easier way, one that I'd seen Scott, NE1RD mention in his blog not long ago.

Tom went back to the truck and returned with what's called a throwbag, which I've got pictured
here. Basically, this is a small pouch that (in this case) has 16 ounces (about 454 grams) of lead shot pellets inside. It's connected to some lightweight and very slippery line, which won't get easily snagged on leaves and branches. What you do is to toss this over a branch, and because the bag is heavy enough, it'll drop down through the branches. You tie your antenna support line to the end of the yellow throwbag line, and pull your antenna into the air. It's remarkably simple, safe (yes, if you hit someone with the bag it's going to hurt a bit, but unless you're very unlucky there won't be any permanent damage to either party), and pretty inexpensive. I found one (pictured here) at the Bartlett Manufacturing website which costs about $17 including 100 feet of line. (I didn't really shop around, there might be better deals elsewhere).

I would have probably have tried to swing it around and toss it up, but Tom used a different
technique. He used the same sort of motion that you'd use when throwing a basketball free-throw shot underhand, rocking back and forth a few times, and then throwing. I think that part of the reason he used that particular motion is because he didn't have a lot of space to work in. The limb that he was aiming for is behind the tree that he's on in the picture, and in order to get over and under the proper branches, he had to get a pretty specific trajectory. It took him several tries, but he managed to get it over a limb that he guessed was about 50 feet in the air. (I'd say it was a good guess, since after the throwbag came down, the 100 foot rope had about half of it on one side of the limb, and about half on the other, with both ends just barely on the ground; even I can divide 100 by 2!). I told him that was amazed at how he was able to get it over the branch, and he said that he was embarrassed because he can usually hit just about anything he wants in one try. Granted he is a professional, but it's still impressive.

One other good thing came out of taking down the antenna. I was able to examine the wire and the support line, which I normally can't see very well, being up in the air and all. The wire looked surprisingly good, and most of the support line was fine, with one exception: About a foot past
where the support rope tied to the insulator, it must have been rubbing on a branch, because it was fairly well worn. I don't know how long it might have stayed up there before breaking, but given that I had some new support line available, I took advantage of the opportunity and decided to replace the old line with new. I've thought about replacing the support line as preventative maintenance anyway, but hadn't planned on doing it on virtually no notice. I was lucky that I had some of the original line that I'd bought when I first put the G5RV up (I had no idea at the time how much I'd need, I think I bought something like 500 feet; all told, I probably used about 200, much of which is coiled up on the eyebolts in the tree where it's tied off. I don't need that much when it's in the air, but I do need it for the rare occasion when the antenna needs to come down.) If this had happened a few days later, I would have picked up some of that nice dark line that's always available at hamfest (the BARA hamfest is tomorrow, as it turns out), but I was happy to have anything on hand.

So, in my case, what went up, came down, but went right back up again. The antenna works just fine (in fact, it might be just a bit higher because the support line is no longer hung up on some branches from the now-removed tree) I was only off the air for a few hours, and I don't have to worry about that particular tree falling on my house.

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