> The solution I use here to tune radials is to insert an RF
Counterpoise Tuner
> (TT-1251) between the coax shield and radial system at the
antenna feed
> point. With low power on the antenna adjust the RF
Counterpoise Tuner for maximum
> current as shown on the meter display.
Won't do a thing for loss. The loss in the radials is fixed
by the current and electrical field density around the
radial regardless of how you play at the feedpoint.
For example the MFJ Artificial Ground doesn't change ground
loss at all. It simply modifies the feedpoint impedance.
Many people have done experiments like this and watched
field strength, and have been disappointed with results.
K8BBI in Cincinatti did it on 160, and found like I and many
others have that maximum current by tuning radials doesn't
mean much. RCA did tests at a VLF transmitting location and
found the resonate ground system they were using was less
efficienct than a simple untuned system.
> Or, you can use RG-58PE (vf.66) to make your radials
electrically measured
> for 1/4 wave as shown on your MFJ-259 (page 30 of users
manual and as shown in
> ON4UN's book). This method is very accurate and results in
the radials being
> 30% shorter in length over using wire.
Won't work either John. If that claim is in ON4UN's book it
is in error. I know that flawed concept appeared initially
in W6SAI's books and articles.
The reason it won't work is radial currents are all common
mode currents. The dielectric inside the coax has no effect
on velocity of propagation or electrical length of the coax
when used as a radial because by electrical rule all common
mode currents must flow on the outside of the shield away
from the internal dielectric.
There is no magic or free lunch to any of this. No matter
how we would like to save work, the fact remains a good
low-loss non-radiating radial system requires a large number
of conductors spread out over a reasonable area in a
straight line. Certainly if we can't do that we might find
some compromise system allows us to be happy, but the rule
is the smaller the system the more problems it potentially
will have.
It's a shame bad articles get published. Once they are in
print, they take on a life of their own.
73 Tom
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