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[TowerTalk] 80m Dipole ssb/cw switching

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Subject: [TowerTalk] 80m Dipole ssb/cw switching
From: W8JI@contesting.com (Tom Rauch)
Date: Wed, 14 Nov 2001 16:32:54 -0500
>  the coax. There are ABSOLUTELY NO RESISTIVE ELEMENTS IN A BAZOOKA OF
>  ANY 
> KIND EITHER. THERE ARE ONLY A FEW SPACERS SIMILAR TO OPEN WIRE LINE
> HOLDING THE BAZOOKA ELEMENTS 4-6" APART.  IT WILL TAKE AS MUCH POWER
> AS THE COAX ITSELF (THAT HAS BEEN FULLY TESTED EVEN WITH RG-58) WITH
> NO LOSS OR SATURATION OF CORES OF OTHER BALUNS--THERE ARE NO CORES IN
> A BAZOOKA EITHER.  

That statement is clearly incorrect, no matter how many capital 
letters are in it.

The vast majority of any broad banding comes from additional loss, 
just as the ARRL Handbook and people like Walt Maxwell and 
others claim.

The problem, as I demonstrated in a post earlier, is it takes a 
VERY low impedance or very complicated stub system stub to 
cancel reactance any noticeable amount. I wish that wasn't true 
because I would use a parallel stub myself, but it unfortunately it is 
true. The Handbook is right, the old wive's tales and rumors are 
wrong.

Anyone who claims a coaxial cable used as a stub, especially one 
made from a small cable like RG-58, is lossless clearly has never 
measured or calculated the terminal impedance of the stub. Even 
open wire stubs, like those used for linear loading, are far from 
lossless.

Anyone who claims a simple shorted stub with an impedance more 
than a dozen ohms in parallel with a dipole can provide significant 
or noticeable reactance compensation has never used a Smith 
Chart or investigated the system.
73, Tom W8JI
W8JI@contesting.com 

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