[Antennas] J-Pole

W1GOR W1GOR at Maine.RR.Com
Wed Sep 29 15:29:15 EDT 2004


John...

We knew all of that... But anything other than coax is impractical from a
measurement standpoint...  How much test gear exists that will provide
reasonable accuracy with ladder-line..?   With the exception of ancient
LECHER WIRES, I can't think of any...(smile)

73, Larry - W1GOR


----- Original Message ----- 
From: "John Tait" <bravo at iol.ie>
To: "Joe" <nss at mwt.net>; "W1GOR" <W1GOR at maine.rr.com>
Cc: <antennas at mailman.qth.net>; "Durwydd MacTara" <durwydd at hotmail.com>
Sent: Wednesday, September 29, 2004 1:18 PM
Subject: Re: [Antennas] J-Pole


> No.. I don't think he's kidding.. The whole point of open wire feeeder is
> that it has very low loss. It is the most efficient feeder type that's
> available to us. Line loss increases with frequency, with SWR,and with
line
> length, so VHF/UHF antenna system have the most to gain by using open wire
> line. Good quality "Ladderline" is a less efficient feeder than proper
open
> wire line, but has less loss than coax..'specially if SWR is high.
>    However.. coax is much simpler to deploy than open wire line, and good
> quality hardline has acceptable losses so long as SWR is low, and lengths
> reasonable. Most of us settle for that, and put up with the losses. We can
> compensate for loss of transmitted power by using a linear amplifier, and
> for RX loss with a good low noise mast head preamp.
>   73
>    John EI7BA      http://www.iol.ie/~bravo/
>
>
> >
> > W1GOR wrote:
> >
> >> Ladder-Line for VHF/UHF...?  You've gotta be kidding..!
> >>
> >> 73, Larry - W1GOR
> >>
> >> ----- Original Message -----
> >> From: "Durwydd MacTara" <durwydd at hotmail.com>
> >> To: <Antennas at mailman.qth.net>
> >> Sent: Tuesday, September 28, 2004 10:20 AM
> >> Subject: [Antennas] J-Pole
> >>
> >> > I have a homebrew 2M/70CM J-pole 50 ft. in the air for use with a 5W
> >> > HT.
> >> Am
> >> > currently using RG-213 for feedline. i am wondering if it is worth
the
> >> > effort to switch the feed to ladder line, and if so how to do it?
> >> >
> >> >   "Carpe` Diem!"
> >> >              Durwydd MacTara
> >> >
>
>



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