Here we go again... so which is it? Inverted L's have plenty of bandwidth or
Inverted L's little bandwidth???
First, let me say if you are not taking your measurements AT THE FEEDPOINT, you
are not seeing the true story. Second, a large bandwidth is not necessarily a
good thing. The longer and more lossy your transmission line, the better your
antenna is going to look from the shack.
Here's an example of what I'm talking about... I have a low 160m inverted vee
which I plotted VSWR graphs at the feedpoint and again at the end of 230 feet
of rg8x coax. I made absolutely no antenna changes between these two
measurements. I posted the superimposed VSWR and RETURN LOSS curves on my
website, here: http://tinyurl.com/oh87y The two PDF files are 72-KB each and
can be downloaded and viewed using Adobe Acrobat Reader.
In this specific example, measuring at the end of the coax leads you to believe
you have 35% better bandwidth than in reality.
73 de Bob - K0RC
> On 13 Jul 2006 13:20 WA3AFS wrote:
> Please be aware that the bandwidth for a coaxial inverted L is very
> broad. My SWR at 1.800 is 1.3 and slowly rises to 1.7 at 2.000Mhz.
But then on 13 Jul 2006 at 13:11, K4SAV wrote:
>> The biggest problem you have with low band multiple L antennas is
>> matching and bandwidth. To start with, a 160 meter L will not have a lot
>> of bandwidth...
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