Subject: Topband: Home Depot RG-6 Cable
Stay away from the low priced RG-6. I used to buy 500 foot rolls of RG-6 Quad
from Home Depot to be used to feed my beverages and K9AY loop.
The cable was made in Canada. Its weakness is its PVC jacket which is easily
scored, nicked, or cut. I found several instances in my system where a small
tear occurred and allowed water into the cable. The outside aluminum shield
quickly deteriorates and a powder starts to form.
The best way to go is to use a flooded cable which I will do for all
replacements. Also, once installed, it is a good idea to measure the total
cable resistance of the installed feedline and record it for future reference
and trouble-shooting. I was surprised at the resistance of the combined center
conductor and shield of a 500 foot length of feedline. It runs in the range of
14 to 18 ohms for RG-6.
73, Dennis W0JX/8
***
Here I have to relate a story concerning F6 (RG-6) CATV cable and topband. A
few years back, I installed the DXE rx 4-square. I installed it at the
compromise 160/80 meter spacing, but I was never happy with its 160 meter
performance - 80 was great. I installed it with Commscope quad-shield, flooded
F6, all from the same 1000' spool, using snap-n-seal connectors. Finally, in
December 2008, I decided to stretch it out to the recommended 160 meter
dimensions, so I needed to cut new runs out to each element and new phasing
lines. I bought another 1000' spool of the same CS cable, and cut all my new
runs, measuring phase with an HP 8743 network analyzer, same as before. When I
got to actually pulling the old cables up from below the leaves and crap out in
the woods, I found several spots where critters had chomped on the cable,
usually just leaving teeth mark punctures in the jacket. But in three locations
(including one spot where I had inadvertently run it right past his front
door), a groundhog had chewed the cable so severely that I could see the center
conductor for a length of an inch or more. I thought to myself: well, damn, no
wonder this thing doesn't work like it should!
Long story short, when I took the damaged cables and put them on the network
analyzer, the phase and attenuation were just like you would expect from new
cable - at 1.8 MHz. Moral: you can get away with a lot at 160 meters.
p.s. - that groundhog is in for an accounting when he emerges this spring...
73,
geo - n4ua
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