Yup, I understand what you are saying and do not disagree. A
clarification please (and this assumes there will be some interaction
between tower and antenna worth worrying about).....were you referring
to how we sometimes "fudge" certain simulations by selecting a Mininec
or perfect type ground (that allows direct contact with Z=0) and then
insert an assumed resistance for that we think are the ground losses
etc? Or were you going to stick to a real, "high-accuracy" type ground
that does not like a connection to ground but make a connection to Z=0
anyway?
Also what value of R should be used ? 2 ohms, 5 ohms, 10 ohms ? Do most
ops really know what an accurate number to use is for our particular
grounded towers, vertical antennas etc ? I suspect many are taking a
best guess at a number and assume it is close & hope for the best.
I wish I had NEC-4 but even so I am half tempted to model this darn
situation just to see for myself what the results will be under
different situations hi-hi.
Gedas, W8BYA
Gallery at http://w8bya.com
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 4/26/2019 3:52 PM, jimlux wrote:
One thing I have not seen mentioned (maybe I missed it) is the fact
that a whole lot of time & effort is going to go into generating a
super accurate model for a complex tower and antenna system but then,
what of the grounding of the tower itself at the base? Grounded or
un-grounded or sorta grounded are all going to give different results.
That's easy to test in NEC. Just put a resistor between tower and ground.
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