In a message dated 96-10-22 14:53:43 EDT, you write:
>Tried to send this privately, but it bounces.
Yes, Eric's address is not taking direct E-mail, hi.
>What's wrong with reducing the number of radials by making each one in the
>form of a Y, branching at the point where the spacing is less than .03?
Bob,
I guess sometimes this stuff comes out wrong but let me try to interject
something that is very important.
Ground loss is totally dependent on the field levels and/or current at every
point in the system. An antenna or radial with standing waves on it acts like
a impedance transformer as well as its' other job. The loss resistance we
*think* we measure at the feedpoint can be wildly different than what really
happens in the system.
Branching wires in a Y might be OK in some cases and not in others. Bunching
the wires in a bundle increases the RF resistance and impedance of the wire,
and if done at the wrong point it can hurt performance. How much is anyone's
guess, but it could never be better than the same number of evenly spaced
wires.
The only way to accurately evaluate any of this is by field strength, since
it is the distributed loss and not the resistance measured at any point that
really matters. Peter's test was good because the earth mounted radials
likely carried low standing wave levels. In other systems, base impedance
could have very little or nothing to do with efficiency.
I hope this makes sense, because it's important.
73, Tom
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