Don't forget, the phase change in a cable is not equal to
the electrical length of that cable if the SWR is not unity.
You will need to calculate the necessary electrical length
of the cable carefully taking into account the mutual
impedances of the verticals (they will be very high for
1/8 wave spacing).
There have been several articles in QST, ARRL Antenna
Anthologies and ON4UN's books on this subject.
73,
... Joe, W4TV
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jerry Muller
> Sent: Thursday, October 20, 2005 12:28 PM
> To: Rex Lint; yv5lix@yv5lix.org.ve; towertalk@contesting.com
> Subject: Re: [TowerTalk] FW: 135 degrees phasing.
>
>
> Exactly Rex. It gets interesting if he's cutting the cables
> for electrical length instead of by physical length. If he's
> doing electrical length by looking for a point where they're
> (n+1)/4 wavelengths long, he can just change the frequency
> that he uses to find the null. I usually do mine by
> electrical length. It takes out the slight differences.
>
> 73, Jerry K0TV
>
> ----- Original Message -----
> From: "Rex Lint" <rex@lint.mv.com>
> To: <yv5lix@yv5lix.org.ve>; <towertalk@contesting.com>
> Sent: Thursday, October 20, 2005 9:06 AM
> Subject: Re: [TowerTalk] FW: 135 degrees phasing.
>
>
> > Joe,
> >
> > Why wouldn't you just add half of a 1/4 wave to a 1/4 wave?
> > 90 degrees plus 43 degrees - 135 degrees.
> >
> > Rex - K1HI
> > Merrimack
> >
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com
> > [mailto:towertalk-bounces@contesting.com] On Behalf Of Jose
> M. Valdes R.
> > YV5LIX
> > Sent: Tuesday, October 18, 2005 8:51 PM
> > To: towertalk@contesting.com
> > Subject: [TowerTalk] FW: 135 degrees phasing.
> >
> > Hello,
> >
> > I'm getting ready for the next CQWW SSB contest and I'm
> > working in phasing 2 1/4 wave verticals for 75 meters and
> > all simulations shows that best gain is obtained with 135
> > degrees phasing, but I would like to know how to obtain
> > 135 degrees phasing with the length of the phasing lines;
> > 90 degrees is easy because it uses 1/4 wave electrical
> > length for the phasing lines, which can be calculated
> > using the velocity factor of the lines used, but 135 is not
> > as easy.
> >
> > I can obtain 90 degrees phasing using two 1/4 wave RG-11
> > and one 1/4 wave RG-8 for the phasing that will be switched
> > using 2 relays, but 135 degrees is another story.
> >
> > 73/DX Jose M. Valdes R. (Joe) YV5LIX
> > eQSL.cc Advisory Board Member
> > QSL manager EA7FTR
> > SYSOP YV5LIX DX Cluster
> > telnet://yv5lix.org.ve:7300
> > VHF Packed: 145.430 YV5LIX
> > http://www.yv5lix.org.ve
> >
_______________________________________________
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
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