> As another suggestion, try radials of two different lengths to give you
> two points of low SWR within the broad 75/80M band.
> Gene Smar AD3F
If you are talking about a vertical, you should be looking for maximum RF
current at the feed point, or better still, maximum measured field strength,
not the lowest SWR. A 50-ohm resistor dummy load will give you a perfect 1:1
SWR.
For example, a short vertical or inverted-L may present something on the order
of 10-12 ohms resistive at the feed point once the reactance is tuned out.
With a 50-ohm feed line, that would show up as a 4:1 to 5:1 SWR, with a GOOD
radial ground system. With a poor ground system having 40 ohms resistive loss,
the SWR will read nearly perfect 1:1. But the good ground system, despite the
mismatch, will radiate a lot more RF than the poor ground system that gives the
perfect match.
More than once I have heard a ham say he tried laying down some more radials to
his vertical, but took them back up because the new radials made the SWR higher.
Don k4kyv
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