> Chuck Counselman wrote:
> >
> > > By running the coax through a wad of steel wool inside a mailing
> > > tube!
> > >
> > Can anyone post quantitative info on this method, e.g., for a given
> > diameter and length tube, packed with how much of what grade steel wool,
> > how many dB of attenuation as a function of frequency?
This idea comes from a QST article that made it into the ARRL
Handbooks.
> Well, this isn't very quantitative, and I don't remember where I saw it,
> but someone recently DID try this in various forms and found it to be
> essentially worthless.
Another magic claim for special metals bites the dust. The article
claimed the steel wool would act like a balun, and help prevent TVI.
Of course it does nothing of the sort, since eddy currents in the
steel wool cancel any magnetic flux concentrating ability at radio
frequencies.
Shredded nichrome would be just as effective as steel wool, as
would any other shredded metal. It basically does nothing at all.
73, Tom W8JI
w8ji@contesting.com
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