More on 2 m antennas, 10m nets
Bob Naylor <wotbob01@...>
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--- On Wed, 1/25/12, Saundby <saundby@...> wrote:
My 40m dipole's high end is about 12 feet off the ground directly below it, attached about 10 feet high on a tree above a steep slope in back of my house. The center is about 25-30 feet above ground, since the antenna doesn't slope as steeply as the ground, and it ends on a short mast about 12 feet off the top of the roof of my 2 story garage, so about 40 feet above ground level.toggle quoted messageShow quoted text
The feedline is 70 feet of RG-8 cable. The antenna itself has a center that's a few inches of solid 14ga wire soldered into an SO-239 socket, which is then soldered and tied to lengths of 3/8 diameter tinned shield braid that make up the main part of the antenna, each half is about 34 feet long, tied off and folded back to make the overall length of the antenna about 67'.
The center wires each have a twist in them after they come out of the connector, with a piece of rope tied between them to keep the strain from the antenna from getting to the connector.
The ends are supported by PVC insulators I made, about 8 inches of PVC tubing each, with holes drilled cross-ways about 1" from each end. On one side of the insulator the antenna wire passes through to be tied back to itself, the other side has some guy wire passed through to tie to the supports. On the high side the guy wire loop goes through a hole in a board that's nailed to a tree high on the slope. On the low side it loops through a bicycle inner tube which acts as a spring, which is then attached to the low mast on the garage roof.
Have I mentioned that I'm a graduate of the Tarzan School of Engineering?
This was pretty much just intended to be a "get it up quick before winter sets in" antenna. The nice weather we keep getting is giving me a change to improve on it if I time things well.
I'm planning on getting a dedicated 10m loop up before Tuesday. I picked up the parts today to make a hanging loop like the one here:
But I'm only making the 10m portion of the loop, not the 17m part, to keep it simple.
I got a chance to see Bill, W6WEM's skyloop today. It was really good to see a real live antenna and get to talk to its owner. I've been reading too many articles on the internet, combining the complexities of each antenna I read about in my head into something a lot more complicated than is necessary. Getting grounded in reality helps keep me from overcomplexifying things. ;)
I'll be measuring some trees to figure out whether to put up an 80m or 160m skywire, then putting in an order with AES or someone to get the parts. If a 160m version isn't going to be too much more effort over an 80m, I think I'll try that. If it looks like trying for a 160 is going to make the project hang fire, I'll just go for an 80m loop now and save the 160 for sometime later.
Bill also gave me a couple of his unused jpoles, one for 2m and one for 440. I'm going to put the 2m jpole on a fiberglass pole and see if I can get in to our repeater with it somewhere on my property. If so, then I'll mount it there permanently.
Amaryllis is going to get the 440. I'm going to get her a dual-band HT for her birthday, and she can borrow my antenna when I'm not using it, and put her 440 up where ever it does something good for her. I'm going to leave that entirely up to her so that dad doesn't get in the way of her figuring things out for herself. ;)
Right now it looks like my "social director" has remembered a commitment we have for this afternoon and evening, so I probably won't get a chance to do anything until tomorrow. I've got a full list, and honestly if I just manage to pull together one thing this weekend that'll be good enough.
If I have a chance to get on the air, I'll let you know and we can see what I sound like. I think Loomis is just over 25 miles from here as the crow flies. I'm not sure what the low height of the antenna and the slope will do to its pattern. It sure isn't getting me out to Grass Valley, but that's on 10m which the antenna isn't really cut for.
--- In W6EK@..., Bob Naylor <wotbob01@...> wrote: