Monday, June 08, 2009

The Tree! The Tree!

Updated:
...The tree with a fat branch over 20' long -- most of it over our neighbor's back yard -- that we knew was cracked. The tree that one day last week went kh'kh'kh'ker-POW! while Tam was reading on the porch mowing the lawn beneath it (!) and lowered said branch into the neighbor's yard, neatly trapping her grill. That tree.

It's getting a bit of a trim and brush-up today, it is. Beseems the neighbor, she is not so very fond of havin' her barbecue grill trapped by a wild Box Elder (or whatever it is; the tree-trimming guys say it's a hackberry, and they should know) and has arranged for Experts (they'd better be!) to remove the offending branch.

This tree supports part of my nice G5RV wire antenna,* in close to the trunk on the same side as but lower than the branch in question. Keep your fingers crossed!
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* This is my second G5RV antenna and until I went looking this morning, I had no idea there was any controversy about them or bias against them. Louis Varney, a British ham with the callsign G5RV (well, duh) developed it before I was born and in his version, it was fed by an antenna tuner -- a widget with a few controls on it that have to be adjusted. This can more-or-less be avoided by putting a long piece of coaxial cable in between the feed point and one's radio but it is a less than perfect impedance match. Newer (read "solid-state") ham rigs do not so very much like that. Long story short, J. Random Ham puts up a store-bought G5RV with 70' of coax feeding it, his YeasKenCom transceiver emits smoke, J. Random proceeds to tell all his pals how the G5RV is No Good. Multiply by a few thousand, add Intarwebz and stir. Yeah. like that. It's never "operator error." When did things with knobs on 'em become Just Too Much for technical hobbyists to frob with?

13 comments:

Tam said...

No, it would have been relaxing had all the crackling and popping occurred while I was on the front porch reading.

Instead, it happened while I was in the back yard mowing. Right under said large branch. Needless to say, I got out from under the tree with a quickness and left the mower to its fate, retrieving it only when the bough had come to rest.

Roberta X said...

Oh. Ooooooh!

Nathan Brindle said...

Operator error crops up everywhere, and nobody likes admitting it.

Try telling one of our customers that they may have a PEBCAK problem. That never goes over well, even if it's the truth (which it usually is).

Turk Turon said...

You said it "lowered". Not "fell". Any impact damage? Glad there were no casualties.

Tam said...

It's still attached (or was, as of 1000 hrs,) to the tree, but in a fairly precarious fashion.

It's supported by bark on one end, and the neighbor's Weber on the other.

D.W. Drang said...

The year after we moved into this place, and I was in Korea (as usual) we had the decennial snow storm, and it collapsed the back porch roof/awning. Mrs. Drang had to wait until the snow melted to actually assess damage; we discovered the dark side of neighbors who "mind their own business..." (I remain convinced that back in the Midwest, neighbors mind their own business, but would check up on each other.)

For several years after, if you looked up our house on whatever the website was that Microsoft had that preceded Google Earth, the satellite photo still showed an awning.

I had always heard that one must use a tuner w/a G5RV, unless it was set for THE freq you are using... Maybe I'll stop referring to myself as an Appliance Operator.

BTW, anyone whose eyes glaze over when you start 'splainin' "Antenna Tuner" to them, if they were in the Army (or Marines, I ass-you-me; flyboys and squids, not so likely) have used an antenna tuner, but called it a "matching unit." It goes from 10 meters to 4.

Crucis said...

I don't have room to hange a G5RV, but I do have a MFJ tuner in-line with my Kenwood TS-570S. I use the tuner for make by verticle usable for 160M RTTY. Other times, the tuner is in pass-through mode.

Works for me. (But, then I've used tube rigs for decades before going completely solid-state. I still have a pair of 6146s around somewhere left over from my Heath SB-102.)

Stranger said...

The G5RV is about as good as you can get - for what it was designed for. A 20 Meter antenna with some gain, that can be pressed into service on 75/40/15/10.

The problem arises when A, newbie ham buys one and thinks he has a world beater 160/60/30/17/12M antenna, or B, thinks he has a champion low band DX antenna.

It's a couple of S units south of an Alpha Delta DX-CC on 75/80, and a third of an S unit up on 20. And tain't worth last years spit on 30.

Stranger

Anonymous said...

Oh, yeah, WARC bands. What were those supposed to be for?

Turk Turon said...

I lost "my tree" two years ago. It was a big old cherry in the corner of my back yard. Due to the layout of the yard, and the need to avoid power lines, I had to find a dipole design that I could feed off-center. A little research led me to the Windom antenna. This is an asymmetrical dipole, fed with 300-ohm twinlead. For a low-power (100-watt) transmitter, this gives an extremely light antenna, just a couple of pounds, and in the air it is almost invisible. It looks like a piece of old TV twin-lead that has become caught in a tree. I used a slingshot to put 80-lb test monofilament into the tree to support it, and it qualified as a truly "stealthy" antenna, ideal for my little house and invisible to my neighbors. I went to the hardware store to get some wire and the guy had a 500' spool of 300-ohm twinlead. I asked him for 50' of it and he begged me to buy the whole spool for five dollars, just to get rid of it. Sold! That stuff can come in handy for a lot of applications: you can build a lot of 2-meter J-poles with it, then slingshot one up into the trees, WAY up over your campground. Anyway, my Windom feedline came down to balun which converted it to coax and then to a miniature automatic antenna tuner, then to the Yaesu 857 transceiver. Worked very well, except on 80-meters, where it was unusable: I didn't have enough room for the long Windom, just the 40-meter version.

But the tree, alas, is gone, and I am reduced to using one of those "apartment dweller" whips out of a second story window. It tunes fine, but has no reach. I'm considering sling-shotting some magnet wire into the next door neighbor's tree in the middle of the night. I was able to get some CW practice from W1AW, but QSO's are hard: the other stations report very weak signals, even though the SWR readings are in the 1.1 to 1.2 region.

Right you are about the modern transceivers, Roberta. They monitor SWR continuously and will reduce power output automatically to protect the final amplifier.

I have been in love with wire antennas since I was a kid. The ARRL publishes a couple of wonderful books of wire antenna designs.

Roberta, you have a truly ingenious layout for your G5RV and I hope that your tree will continue to support it.

Incidentally, box-elder trees attract swarms of box-elder beetles, harmless but disgusting little creatures, which swarm over the trees, and nearly houses in the summer by the millions.

Roberta X said...

According to the tree guys, what's in my back yard is a hackberry, a member of the elm family. They don't take well to injury, so it's hard to say what effect the branch removal will have on it.

Turk, I wonder if you could manage a wire vertical up the side of your house? Probably have to add a counterpoise but it might do for 20 and 10.

Crucis said...

I'm space limited to an extent---no good trees for a dipole or other wire antenna. I've used verticals for years---currently a HypGain DX-88. You can add a base loaded coil for 160M but a tuner works just as well. I used surface tacked chicken wire for a ground. Tack down, seed grass and the wire becomes invisible as long as no tries to dig in that area.

I have to replace that wire every five years but it works very well.

og said...

When I read the post header all I could think was "The (ground)Plane! The (ground) Plane!"

yes, I know a dipole doesn't need a ground plane. I still hadda say it.