Relevant to this discussion is an extensive study conducted by US Navy:
THE MITIGATION OF RADIO NOISE AND INTERFERENCE FROM ON-SITE SOURCES
at RADIO RECEIVING SITES (November 2009) by Wilbur R. Vincent, George F.
Munsch, Richard W. Adler, Andrew A. Parker. (By the way, each of the
study's authors is a ham.)
The authors surveyed noise floor problems at 40 Navy receiving sites around
the world. They drew on data from thee Navy's
Signal-to-Noise-Enhancement-Project.
They had many recommendations and conclusions. But the most relevant to
the original question of this thread is this one:
*"5.3 Cable Leakage*
*Leakage of noise and other spectral components into RF cables running from
antennas to receivers has been noted at all receiving sites that use
single-shielded coaxial cables. Receiving sites using high-quality
double-shielded coaxial cable and properly-assembled coaxial connectors
seldom encounter cable-leakage problems." *
I am currently in the midst of replacing my "single-shielded coax" with
"high-quality double-shielded" RG400.
I recently purchased 200 feet of Harbour Industries RG400 from Electro
Enterprises, Inc. for $1.43 per foot. It came with certification as
factory new MFG certificate.
A link to the US Navy study can be found at:
http://www.arrl.org/radio-frequency-interference-rfi
(scroll down to bottom of page under heading Naval Postgraduate School RFI
Handbooks)
73, Alan K0AV
alan.higbie@gmail.com
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