I just started using the ARRL provided program, mobile.exe , for
some
mobile antenna design work. I see that one of the figures required
to be input is ground loss.

Which raises the issue for me, how does one measure, ( or
calculate),
the ground loss in a mobile antenna.

I am working primarily with 80M mobile antennas on medium sized
motorhomes.


My thanks to those who have already replied to the above question. To
re-iterate, I was using ARRL's mobile.exe program to model some
proposed antennas for my RV. I don't yet have a design built. Ground
loss resistance is one of the parameters to enter.... and entry
difficult to figure without a physical antenna, it appears.

My proposed antenna will be primarily for 80M. It will be center
loaded, approximately 8 to 12 feet tall, with a 4" diameter air wound
coil ( coil parameters can change ), and will be mounted such that the
FEEDPOINT/base will be at the top of my rear ladder, which is about 10
feet off the ground. The ladder is well bonded to the under chassis of
the vehicle. I may use a capacity hat at the TOP of the antenna... or
maybe not. I am wondering how ground loss/resistance is effected by my
having the bottom/feedpoint of the antenna so high off the ground, not
to mention, I wonder how to calculate or guess what it is at all.

Ed


This is what I am proposing to build.