[Antennaware] Testing the theory..

[David Gould]

Following on from the antenna modelling I did a with EZNEC a few 
months back I am now building the antenna and planning the ground 
system.  I want to do some measurements of the antenna (approx 48ft 
vertical) with different ground system components.  I can measure the 
differences in feed impedance easily enough (I use Larry N8LP's 
LP-100 vector RF wattmeter).  In addition I want to measure the field 
strength with the different ground system components as well. (also 
using the LP-100).   My question is how far away from the antenna 
should I measure the field strength?  I am primarily interested in 
160/80/40m Two options spring to mind...
1) A friend just over 1 mile away
2) I could set up in the back of my car about 400yrds away.

Any thoughts or advice would be appreciated.

73,
Dave G3UEG