On Tue, 10 Feb 2009 16:04:16 GMT, "JB" wrote:

You might want to consider using RG-6/u instead of RG-59. These daze,
the quality of RG-59 coax is rather marginal. I've seen 80% coverage

Beware of the Aluminum foil and shields though. Once it gets wet there is
no stopping the internal corrosion and will generate broadband noise under
power. This includes both RG6 and 9913 and LMR types. They have been
banned from all commercial sites around here.

Amazing. I can see it's possible to create a diode mixer junction
with electrolytic action between the aluminum foil and copper braid.
I've never seen broadband noise from coax cable. Usually the foil is
mylar or polyester coated and the copper is tinned or silver plated to
eliminate any points of contact. Most of the radio sites I've seen
are stuffed LMR-400 and LMR-600. Heliax is better, but also far more
expensive. Incidentally, if you want to generate RF noise and mixing,
there's nothing better than an abraided Heliax outer jacket, with the
copper shield touching the zinc galvanized tower.

If intermod were really a problem with foil shielded coax, then the
common residential CATV distribution system would have a big problem
with intermod and mixes. While the buried coax is semi-rigid with a
solid aluminum shield, the pole to house drops are usually quad
shielded RG-6/u (sometimes with a messenger wire) with foil and braid
shields.

Bring a knife with you and inspect before you buy. Tinned Copper braid is
better, Silver clad rigid is best.

Mylar or polyester coated aluminum foil is more important. Scrape the
insulation and see if it flakes loose from the foil. I've seen this
on very old 9913 and some new LMR-400 of dubious origin.

Slight change of topic.... do the commerical sties that ban foil
shielded coax also ban nickel plated connectors? Just curious.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS