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[TowerTalk] Balun filler

To: <towertalk@contesting.com>
Subject: [TowerTalk] Balun filler
From: jimlux@earthlink.net (Jim Lux)
Date: Fri Jul 11 14:55:33 2003
And even better, there is a detailed data sheet with derating and 
impedances on it..
http://www.cal-av.com/baluns-EB1-ds.html
I do have a question about the term "reactance"...

Does this mean if I hook an impedance bridge between, say, the shield of 
the SO-239 and the black wire, that I'll measure some combination of L and 
R the magnitude of which is around 1K?

It's also unclear whether the voltage rating is from connector to ground 
(case of device) or from coax shield to coax inner conductor.  500V isn't a 
huge amount of power into a 1.4 K reactance..(a bit more than 100W) If I 
were running a kilowatt to a somewhat unbalanced 10 m dipole that put 10% 
of the power on the outside of the coax (say, by mutual coupling), and the 
balun happened to be at the wrong point, wavelength wise, you could easily 
get 500V..

1:2 SWR is a return loss of 10 dB (i.e. a tenth of the power is reflected back)
1:3 is 6 dB (i.e. a quarter of the power is reflected back)..


However, at least they give a spec...

At 02:32 PM 7/11/2003 -0400, TexasRF@aol.com wrote:
>3kw baluns inside pvc pipe filled with epoxy are available from Texas Towers
>for $39. Manufacturer is Cal-Av Labs and same as supplied by Force 12.
>
>tnx/73 de Gerald Williamson/K5GW/Texas Towers

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