How strong is this line?
It is rated like all other fishing line - in breaking strength - in the link I posted it is offered in 30 lb and 45 lb
Can it be used for a dipole or inverted "V" dipole?
I have a elevated ground plane for 30M and a longish Inverted L for 160M - no failures and the Inverted L has a very long horizontal element.
How about for ground radials?
I don't know - I guess it would work well as it is very flexible.
Is this line pure copper or an alloy?
Again - I don't know - I would assume so as pure copper would be very weak and VERY expensive.
<snip> can it be soldered.
Yes - I twist and solder all connections with no problems. I make sure I don't get solder up in the area that bends and have had no failures (yet).
Clint - W5CPT -