And all the time I thought that this was just an early effort to develop a
log periodic system to eliminate the shortening of the first dit when
sending over 20WPM!<GRIN>
73,
Frank, K4VMO
----- Original Message -----
From: "Robert & Linda McGraw K4TAX" <RMcGraw@Blomand.Net>
To: <wb2vuf@qsl.net>; <tentec@contesting.com>
Sent: Friday, April 16, 2004 10:29 PM
Subject: Re: [TenTec] 450 Ohm feedline
> If one remembers seeing the many "signal lines" that ran along beside of
the
> RR tracks, they had a insulator arrangement with a metal support in the
form
> of an X which was used to swap the conductors.
>
> Bob, K4TAX
>
> ----- Original Message -----
> From: "Bwana Bob" <wb2vuf@qsl.net>
> To: <tentec@contesting.com>
> Sent: Friday, April 16, 2004 9:22 PM
> Subject: Re: [TenTec] 450 Ohm feedline
>
>
> > Yes, even before bundled cable, when long parallel lines were run on the
> > telephone poles, the wire positions on the poles were periodically
> > interchanged. One wire was dropped under the other and crossed over to
> > its opposite side by means of a "drop bracket".
> >
> > Hey! Maybe this is the solution to BPL interference: Make the power
> > companies twist the power lines!
> >
> >
> > 73,
> >
> > BoB WB2VUF
> >
> > JAMES HANLON wrote:
> > >
> > > Bob wrote:
> > >
> > > > Regarding twisting the feed-line, why do you suppose the phone
company
> > > > called it "a twisted pair"? Answer: because that what it was and it
> was
> > > > used to maintain symmetry and thus reduce induced voltage from
> overhead
> > > > power lines. Same applies here.
> > > >
> > >
> > > I'm an old Bell Labs engineer, and I can recall being taught in our
> "CDT"
> > > (Communications Development Training) courses that the pairs were
> twisted to
> > > cut down on the cross talk from other pairs bundled into the same
cable.
> > > I'm sure it helped for power line induced voltage as well though.
> > >
> > > Jim, W8KGI
> > > _______________________________________________
> > > TenTec mailing list
> > > TenTec@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/tentec
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>
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