The Shadow wrote:

...
"What gauge of insulated wire do I need to build a long wire for 20, 40,
80 meters.

In the past, I was able to purchase large coils of aluminum wire; I
think it was used for either clothes line (and had a plastic covering on
it), or the aluminum fencing wire.

I don't remember the gauge, or if they even gave the gauge, but it
seemed to be #8 or #10.

It was cheap and light, worked well with the proper soldering
techniques. Or, properly protected clamp connectors.

Since, I have looked for this wire and not been able to find it in lowes
or home depot, orchard supply, etc.

Anyone know a source?

JS