On Jan 5, 9:56*am, Billy Burpelson wrote:
Billy Burpelson wrote:
RHF wrote:
FWIW - Burying the Coax Cable is simply one of the many
Synergistic Elements that goes into making a Low Noise
Shortwave Radio Listening (SWL) Antenna -a-la- John Doty
Three Rec.Radio.Shortwave Messages to Read -by- John Doty
http://groups.google.com/group/rec.r...bc6a2bf8acc12d
Well, "John Doty" in the reference above says:
Any *unshielded* [my emphasis added] conductor in your antenna/ground system is capable
of picking up noise: the antenna, the "lead-in" wire...
First of all, isn't the "lead-in wire" (coaxial cable in this
discussion) -shielded- ? So according to his -own- statement, coax
shouldn't have to be buried, at least from a noise mitigation viewpoint..
Doty continues:
You can keep noise currents away from the antenna by giving them
a path to ground near the house, giving antenna currents a path to
ground away from the house, and burying the the coaxial cable from
the house to the antenna.
In the 1930s, Bell Laboratories, while investigating power line
influence on telephone cables, proved that burial had NO effect on noise
being induced into the telephone cables; i.e., 20 feet of aerial
separation, from a noise standpoint, was exactly the same as 18 feet of
aerial separation plus being buried 2 feet deep.
Hmmm...should I believe "John Doty" or Bell Labs? You're a smart guy --
I'll let you figure that one out for yourself. * :-)
dxAce wrote:
Or, you might believe the 1990's rather than the 1930's :-)
- Well, I don't know about the "1990's" (isn't this the 2000s?),
- but it became a big issue in the 30s due to the rapidly
- expanding electrification of America.
John Doty wrote his 'stuff' in the 1990s.
- In any event, I'm sure that even the most superficial research
- on your part will show that the applicable Laws of Physics
- have not changed since then.
BP -wrt- The Applicable Law of Physics:- No They Have Not.
Undeniable Fact # 1 - The Man Made RFI-EMF Environment
Has Changed Greatly : Increasing one or two Magnitudes from
the 1930s to the 1990s.
Undeniable Fact # 2 - Man's Ability to Accurately Measure the
RFI-EMF Environment and It's Effects Has Changed Greatly :
Increasing at least a Magnitude from the 1930s to the 1990s.
super-ficial-ly yours ~ RHF