May 14th 06, 02:12 AM
posted to rec.radio.amateur.antenna
Yuri Blanarovich
Posts: n/a
FIGHT? Here is another W8JI myth bone!
Howdy antenna aficionados!
Wanna FIGHT?
Here is another misconception propagated by "guru" W8JI, like "there is no
electrostatic shielding, the grounded piece of tubing (shield) IS the
antenna."
Let the games begin! (I will hold my horses for a while :-)
If you read carefully you'll see no has ever said the shield
and how the shield is connected won't change the system when
the system is not designed correctly. When the feedpoint is
done correctly, the presence or absence of a shield has no
effect at all on the system. All the stuff about the shield
"filtering" the fields and blocking the electric field is
nonsense. But some construction methods do result in better
loop balance.
The characteristics of an improperly done feed system are
affected by the construction of the loop, but that isn't
because the shield is necessary or that a solid shield
behaves differently than braided shield. It's because
something was more wrong with the construction in one system
compared to the other, not because of the shield quality.