I suspect the old timers have seen this , but there is a reference article
from Janyuary 1936 Proceedings of the IRE by Chamberlin and Lodge - The
Broadcast Antenna - that addresses many of these questions.
There is a chart in the article that shows output signal in mv/meter versus
ground system radius for various height radiators with a fixed 1 Kw input
power.
It covers radiator heights from 1/10 to 1/2 wavelengths and "ground system"
radius from 1/10 to 1/2 wavelengths.
Unfortunately my notes don't show how many radials in the "ground system" ro
any other details , and the last time I tried to get an old IRE article from
the ASU library they looked at me like I was nuts. Since I retired I don't
have access to any of the retrieval subscriptions anymore.
I have a copy of the chart in my old notes and could convert it to an excel
spreadsheet/chart or simply scan in my graph and make a jpeg file to send
direct to interested parties.
A couple of data points. For ground system radius of 1/10 to 1/2 wavelengths
and a radiator height of 1/10 wavelength , the signal went from 120 to 142
mv/meter almost 1.5 db. And for same ground system and 1/4 wavelength
radiator it shows 149 to 225 mv/m about 3.6 db. The field strength versus
ground system radius plots are straight lines on linear /linear graph. He
only showed ground system radius of 1/4 to 1/2 wavelngth for a 1/2
wavelength radiator but it looks like that could also be straight line if
extrapolated to 1/10 wavelength ground system . Anyhow for those conditions
it shows 225 to 273 mv/m .
Rgds... Hank
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