As Steve said , separate feedlines are the way to go.
This topic has been covered by LB Cebik W4RNL
at http://www.cebik.com/quad4a.html
Hope this helps.
73 Danny - ON7NQ -
[email protected]
http://users.pandora.be/ON7NQ
----- Original Message -----
From: "Brown, James E LRDOR" <[email protected]>
To: <[email protected]>
Sent: Tuesday, February 05, 2002 3:38 PM
Subject: RE: [TowerTalk] Question about triband Quad.
>
> How would the receiving capabilities of this antenna be effected, if at
all,
> by having the one feedline as opposed to separate feedlines?
>
> Jim W4LC
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]]
> Sent: Sunday, February 03, 2002 1:02 AM
> To: [email protected]; [email protected]
> Subject: Re: [TowerTalk] Question about triband Quad.
>
>
>
> In a message dated 2/2/02 6:23:59 PM Pacific Standard Time, [email protected]
> writes:
>
> > I have recently put together a 2 element triband quad. 20 & 15 M work
> good,
> > with a under 2.0:1 over full band (<1.4 over most).
> > 10m VSWR is unacceptably high (3:1 or so over full band.
> > I have checked all connections and dimensions, all OK. Feed is a single
> feed
> >
> > line through a balun and then a length of 75 ohm twinlead to a common
> > connection of all three bands.
> > I arranged to isolate just the 10 m DE, and it shows a 2:1 VSWR over
> band.
> > I was under the impression such antennas were common an presented a
good
> > match on all bands. I plan to test the balun soon, and also
considering
> a
> > 2:1 W2FMI transformer.
>
> You'll have problems when you feed a quad with the feedpoints tied
> together and using one feedline; the 20M loop will radiate when you're on
> 10M
> (14 & 28 mHz). Use 3 feedlines and your problems should be minimized.
>
> Cheers,
> Steve K7LXC
> Tower Tech
>
> ________________________________________________________________________
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> ________________________________________________________________________
> Where do you get ICE bandpass filters & beverage matching boxes? The
> same place that pays for the hosting of this list: The eHam Store.
> Order online at http://store.eham.net.
> -----------------------------------------------------------------------
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> Submissions: [email protected]
> Administrative requests: [email protected]
> Problems: [email protected]
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>
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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