>I believe it was John Belrose who wrote in QST Technical Correspondence
>several years ago. He measured and reported that the topology as used in
>ham LP filters had a minimal effect on performance at to at least a 2:1
>VSWR.
>
>I would be concerned with high VSWR on 10/15M.
>
>I'll bring in a ICE filter to work and play on the network analyzer with
>various resistive loads.
Thinking more in depth, perhaps it doesn't matter so much. At the VHF
frequencies of interest where you want the atennuation to occur, any HF
ham antenna is likely going to look like a HORRIBLE VSWR anyhow. So you
won't be in a 50 Ohm system. And outside of its passband a filter
doesn't have a 50 Ohm input or output impedance anyhow. It's more like a
dead short!
So yep, I am likely concerned about nothing.
73,
Jon
KE9NA
--------------------------------------------------------------------------
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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