TheRadioBoard

My first post to this wonderful board.

As part of my scrounging for as many free parts as possible for various radio projects (crystal, MW and SW DX for now, working toward ham), I learned that my local electric utility now brings all used power poles to their main yard, and gives them away free from there. (They used to leave them for the adjacent landowner.)

They also give away any parts on poles, which means that for an hour's worth of pulling big fence staples, I obtained a 35-foot and a 25-foot length of weathered but intact AWG 6 copper wire, plus pieces of around 6 feet. I also got four round copper-sheet ground plates, with intact setscrew that clamps to wire; these are fastened to the butt of the pole. More than 7 inches in diameter, not sure of guage but I would have trouble bending one by hand.

Questions:

1. Besides a great ground wire, what else can I do with AWG 6? A really rugged loop?

2. Would the ground plates be advisable for antenna ground? I use an 8-foot rod for my main ground, but I'd like to add a separate ground for 75-foot AWG 14 inverted L, and could go down 3 feet with a post hole digger to use the plate as a ground. But I'm not sure if that is deep enough, even with lots of clay in our subsoil. (They'd make an interesting variable cap....)

3. They replace poles all the time, and thus there is a steady supply, though at some point I may need to pay scrap value or show them how I use the free stuff. So, if you had a continuous supply of used AWG 6, what antenna projects would you design and build?

Thanks for any thoughts.

TDane

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God made us able to listen to one thing while doing another, so radio is a divine gift.

> 2. Would the ground plates be advisable for antenna ground?

I don't see any reason why not. Is your clay wet or rock hard? If you go the post hole route, be sure to cover the plate with some "kitty litter" which
is very hydroscopic (absorbs moisture) before back filling the hole. You'll have a good ground for a long time.

73, J.B., VE3EAR

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To be where I am, I had to leave where I was!

I've probably violated every rule concerning "overgrounding". I never turned down copper pipe and wire. I use ground mats extensively. My front lawn has 800 feet or so of wire in the thatch, under my inverted ell. When I get ambitious, I'll lay some more. The small yard in the back, maybe 300 feet. Last year, I made "fishbone" assemblies out of left over copper pipe, and put them down before pouring a new sidewalk. Think and research out not down with grounding/counterpoise schemes.
Mike AD1OS

Is it true, in general, that counterpoise is more necessary and helpful when soils have poor conductivity, because too dry, etc.?

Yes, but no soil will ever conduct like copper. Good grounds are important in two radio areas, for the same reason: The more current you can cause to flow through the antenna, the better.

For a crystal set, all the power you will ever have is what's flowing through the antenna-ground system. Once your antenna is as big as you can make it, improving ground conductivity increases current flow from the antenna to ground (and back -- rf is a.c.) and induced more power into the radio's tuned circuits.

For transmitting, especially with vertical monopole antennas, ground resistance appears in series with the antenna, reducing current flow and radiated power. Too much power is being soaked up by the ground.

With high-gain superheterodyne, or even regen receivers, the effects of a poor ground are less noticeable. You still hear lots of signals, loud enough to easily copy them. Improving your ground system can have amazing effects, though, even if you only listen.

73,

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