[TowerTalk] Balanced Line using Coax ?

[Jim Lux]

At 10:19 PM 7/29/2003 -0700, Chris BONDE wrote:


>Date sent:              Tue, 29 Jul 2003 10:40:01 -0400
>From:                   David Jordan <wa3gin at erols.com>
>To:                     k1ttt at arrl.net
>Subject:                Re: [TowerTalk] Balanced Line using Coax ?
>Copies to:              towertalk at contesting.com
>
> > Hi Boys,
> >
> > Anyone of you actually used coax in this configuration?  I have.  Fed a
> > 40m loop, tri-band Quad,  mono-band beam and 160m dipole.
> >
> > The loops were fed with the shields tied together at the antenna but not
> > connected.  At the tuner side the shields were tied together and
> > connected to ground.
>
>What is really meant by, '.. tied together ...  but not connected...  '?
>
>Also, if you twin lead is, say 600 ohm 6in apart do the centres of the 
>coax have to
>be 6 inches apart ?

Once the signal is "inside" the coax, it matters not how far apart they 
are.  The impedances are determined by the coax.  However, from a spurious 
currents carried on the outside of the shield standpoint, keeping the coax 
close together is a "good thing".