Hi Press. You are right. Once Tom converted the numbers to db, the 213
results didn't look right. When I had done the tests I was only interested
if everything seemed to be in the ballpark and working okay.
Just went out to the tower. What I thought was 213 is RG8 foam. Now it makes
more sense. I had bought a spool of LMD-400 in case the coax, other than the
hardline had a problem, but would up leaving it on the spool, for now.
73,
Tony
-----Original Message-----
From: owner-towertalk@contesting.com
[mailto:owner-towertalk@contesting.com]On Behalf Of n4kg@juno.com
Sent: Thursday, December 20, 2001 15:19
To: TOWERTALK@contesting.com
Subject: Fw:[TowerTalk] Cable Loss Comparison (Was 9913 reliability)
--------- Forwarded message ----------
From: n8ug@juno.com
To: n4kg@juno.com
To: <towertalk@contesting.com>
Date: Thu, 20 Dec 2001
Subject: Re: [TowerTalk] Cable Loss Comparison (Was 9913 reliability)
Hi Tom
The data are right in the ballpark for all but the 213 - no real 213
is gonna show better than 1.3db/100ft - so "very interesting indeed!"
Press N8UG
(I have the MIME problem on my LT and can't post on TT
unless I figure out how to change it - no time to fiddle!)
On Thu, 20 Dec 2001 12:26:47 -0600 n4kg@juno.com writes:
>
> Thanks for posting your measurements Tony.
>
> I converted your percentages to dB total and dB/100 ft
> as shown in the following table. For your 220 ft runs,
> it looks like there is little benefit to using 9913 over
> RG213 and little benefit in using 7/8 inch hardline over
> 1/2 inch hardline. The 1/2 inch hardline offers 1 dB
> less loss than 220 ft RG213. Very interesting result.
>
> Tom N4KG
>
> Cable (avg 220 ft) dB loss dB/100 ft at 10M
>
> 7/8" hardline - 88% 0.555 0.25
> 1/2" hardline - 82% 0.86 0.39
> 9913 - 68% 1.675 0.76
> RG-213 - 65%. 1.87 0.85
>
>
> On Thu, 20 Dec 2001 "N2TK" <t.kazmakites@verizon.net> writes:
>
> Just had tilted over the tower to replace some antennas. Checked
> the coax for loss. Measured the power going into the coax and
> measured the power at the end of the coax at 28.0 MHz with
> a dummy load on the coax. Used the same watt meter for both.
> The length of the coaxes is about 210 - 230'.
>
> Here is the loss as a percentage of power out/power in.
> By the way, I cut off the end of one of the 9913 runs at the house
> (lowest point of run) to see if any discoloration of the copper.
> There was none. This coax has been up for 8 years.
> > 7/8" Prodelin hardline - 88%
> > 1/2" Prodelin hardline - 82% - 2 runs measured the same
> > 9913 - 68% - 2 runs measured the same
> > RG-213 - 65%.
> >
> > The measurements are approximate and were done to just check to
> make sure the coax didn't have a problem.
> >
> > Tony (N2TK)
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