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Old April 25th 12, 08:56 AM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Oct 2009
Posts: 707
Default Indoor Counterpoise For Random Wire Antenna


"Irv Finkleman" napisał w wiadomości
...

MFJ, in the MFJ-1625 Manual say....

QUOTE
It is always important to have a good RF ground,
provided by the counterpoise, when using any
whip or long-wire antenna. This is because the
MFJ-1623 tuner needs something to "push"
against in order to force current into the antenna.
If a good RF ground is not available, RF will usually
find its way back into the power line (RFI),
transmitter audio circuits (RF feedback),
or the operator (RF burns). Water pipes provide
good dc and ac safety grounds, but they are
often inadequate for RF grounding because they
are long single conductors.


You wrote: " I have a nice role of #18 wire, the end is connected to the
tuner, and it is my
intention to unroll it along the floor through my suite until such time as
it is properly
tuned."

So it will be: "a long single conductors"


RF grounds
require large "spread out" surfaces with direct
multiple connections to the equipment ground
point. Water pipes, heating ducts, or multiple
ground rods may work (especially if they are all
connected together with jumper wires), but the
best RF grounds are radial systems or
multi-wire counterpoises.


So you should not unroll it but have "all connected together with jumper
wires".

Jta is the same opinion: "You shouldn't need to unroll the wire at all since
you're using a tuner.
Just hook it up and tune away."
The hook = jumped wire.



P.S. In a previous topic where the matter of electrons
escaping from the end of the antenna was hotly
debated,


I'm sure Tesla and Marconi could have used some of
my simple practical solutions like this one, and perhaps
negated the necessity of long discussions re electrons
escaping from antennas.


There was also Sir Oliver Lodge. He demonstrated the escaping of electrons
from the antinodes (see Fig. 2):

He also discovered that HF do not like the long conductors;
"The electrical charge stored in the Leyden jars could flow either through
the very low dc resistance path provided by the loop of wire or it could
flow across the very high resistance path through the air between the
spark-gap terminals at B. It would seem that the obvious path for the charge
to follow would be through the low resistance wire loop. Surprisingly, Lodge
was able to produce very large sparks across the spark-gap, B, even though
the dc resistance of the wire across the gap was only a fraction of an
ohm.[4]"

I am trying to "descend you into the same bottomless pit"
S*


 
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