Having worked electronic facilities where the ground resistance has to
be less than 5 ohms, I've tried a lot of tricks to get the resistance
down. There is no sure-fire trick to the process, but rod diameter is
WAY down the list of possibilities. The number of rods (up to 12) and
the depth of the rods (sometimes 40ft) is the usual key, but if that
doesn't work try pouring 25lb of salt in a hole next to the rods and
water it good. Salt is a good conductor & decreases ground resistance.

Bob S.

use copper or stainless rod other wise the steel rod will disappear.t
like my old car did