Hi Barrie, et. al.,
I agree with Bill, W4ZV. I would run radials to the fence and connect
them to the bottom of the chain links. If the galvanizing is good you can
solder them. If not, use a clamp and some contact grease. I think that
helped me at my old qth with a fence only 40 feet from a shunt fed tower.
Good Luck George K8GG