It would be interesting to see actual loss of Belden 8267 RG-213. I only
use it for jumpers and rotator loops and I use Heliax for long runs.
Johh KK9A
To:towertalk@contesting.com
Subject:Re: [TowerTalk] Coax
From:Jim Brown <jim@audiosystemsgroup.com>
Reply-to:jim@audiosystemsgroup.com
Date:Sun, 08 Apr 2012 21:11:58 -0700
List-post:<towertalk@contesting.com">mailto:towertalk@contesting.com>
On 4/8/2012 9:01 PM, Jim Thomson wrote:
> LMR-400db .666 db
> LMR-400UF .799 db
> RG-213U 1.024 db
RG213 is not a spec, it's a very broad generic description. There are
RG213s built with thin copper braid and others with heavy copper braid.
The loss in cable is a direct function of how much copper they use to
build it. Based on resistance data, Davis's 213 is directly equivalent
to LMR400 for use on the HF bands.
## say what. Run 200 feet of 213-U into a dummy load at the far end,
with
a wattmeter 1 foot before the dummy load.
You'll need far more precise instrumentation than a Bird to measure a
difference of 0.1 dB Rather, you'll need a scope, RF voltmeter, or
spectrum analyzer that can resolve 0.01dB, you'll need to measure by
substitution, and you'd better make a bunch of measurements and compare
them.
73, Jim K9YC
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