I have been watching this thread with interest, I am preparing to put up a
receive array and it will have to be some distance from the shack.
Is there a brand of RG-6 that someone has tried that is recommended?
Or some idea of a good name to look for.
Shipping to Molokai is more than 1000ft of coax costs, so need to make
the right choice the first time.
Not sure at this point of exact feedline length but will be more than
1000 ft.
I see commscope RG-6 burial type orange on Ebay, anyone tested that and
is commscope decent material? I will have to bury it due to mongoose
chewing on most anything laying on the ground, they chewed through teflon
coated wires for beverages that laid on the ground overnite before getting
erected.
Thanks 73 Merv K9FD/KH6
Several topbanders asked if I would measure the DC resistance of the solid
copper and copper clad steel center conductors of the RG-6 coax for which I
published the RF loss measurements. I also measured the quad-shield DC
resistance, both cables measured the same.
Here are my measurement results:
Solid copper: 0.6 ohms per 100 feet
Copper clad steel: 1.9 ohms per 100 feet
Quad shield: 0.3 ohms per 100 feet
It appears that copper clad steel RG-6 is a good choice for remote powered
preamps and relays except for very long cable runs.
When using a remotely powered device its extremely important to prevent even
the slightest moisture entry. RG-6 compression connectors are NOT waterproofed
at the threaded end of the connector, additional waterproofing is absolutely
essential.
The Thomas & Betts NS500 Nut Seal costs only a few cents and it very
effectively waterproofs the connector threads.
http://www.ebay.com/itm/NEW-LRC-AUGAT-THOMAS-BETTS-NS-500-NUT-SEAL-50-LOT-/160703026841
The inside of the connector should be stuffed with STUF Di-Electric Filler to
prevent moisture accumulation from condensation. The finished connection
should first be wrapped with electrical tape, then a final layer of
waterproofing should be applied such as Coax-Seal moldable tape.
73
Frank
W3LPL
---- Original message ----
Date: Wed, 23 Jan 2013 17:58:31 -0500 (EST)
From: <donovanf@starpower.net>
Subject: Measured RG-6 Loss: Solid Copper vs. Copper Clad center conductor
To: topband@contesting.com
Today I measured the difference in loss (dB per 100 ft) between solid copper
(SC) center conductor RG-6 vs. copper clad steel (CCS) Quad-Core RG-6 coaxial
cable. The difference is not significant until cable lengths exceed 350 feet.
You can see the affect of the steel core at 7 MHz and below in this table.
The cables were manufactured by two different companies, but the relative
measurements should be valid.
Solid Copper Cable length in
Freq Copper Clad feet for a 1 dB
MHz Loss Loss loss difference
1.8 0.3 0.6 350
3.5 0.4 0.6 500
7.0 0.6 0.8 500
10 0.7 0.85 650
14 0.75 0.9 650
21 0.9 1.0 1000
28 1.0 1.1 1000
73
Frank
W3LPL
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Topband Reflector
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Topband Reflector
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