At 09:01 AM 1/18/99 -0500, w8ji.tom wrote:
...
>I think marketing and folklore has us all convinced stubs are lossless.
>Just like lumped components, ALL stubs have loss. Coaxial cable stubs can
>be particularly lossy. They just have so much surface area, they spread the
>heat around so the temperature rise isn't great.
Interestingly, in the W9LT/K3LR-design lazy-vee parasitic array, the losses
in the floating feedlines of the non-driven dipoles (which are
open-circuited stubs) actually improve F/B ratio substantially (though at
some cost in gain). You can see the change dramatically if you model the
feedlines as transmission lines (which are lossless in NEC-2) and then
replace them with loads of the appropriate X and R values.
73, Pete Smith N4ZR
[email protected]
Loud is.
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