No good grounding is possible fo the base of the antenna. So I decided to
use the MFJ-931 artificial ground as a substitute.
The artificial ground is designed to tune a 1/4 wave counterpoise to present
a low impedance rf ground to the chassis of the rig. This is usually done by
cutting the 1/4 wave ground wire to something less than 1/4 wave length. Then
the artificial ground (series resonant circuit) is tuned so it looks like a 1/4
wave radial, or counterpoise. The tuning is done by looking for maximun
current in the counterpoise.
If you are only interested in a single band, just attach a single wire radial
1/4 wave long and forget about the artificial ground. If you want maximum
performance from a screwdriver or any type of vertical, a good ground system is
necessary, but you already knew that.

73 Gary N4AST