Any antenna, the longer the coax, the easier to tune, not really a good
thing since what's actually happening is with the SWR being high at the
antenna, and the end of the coax, you're losing the signal along the coax,
it's turning in to heat and you're just losing signal along the long run of
coax. That's why with some G5RV antennas they need a certain length, make
the run too short you'll never do it with an internal tuner. Over all
performance wise, probably about the same if not better still with the
shorter run of coax and external tuner. I would never, ever run more coax
than is needed to make it from the radio to antenna, how ever you do it.
----- Original Message -----
From: "Jim Shaffer" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, January 25, 2014 9:39 AM
Subject: Just purchased a Zerofive vertical
> Well I just bought a 29 ft. Zerofive vertical for 6 =E2=80=93 80 meters. =
> That fits our HOA regulations. Now I need to get some coax. The web =
> page on the antenna says I should have a minimum of 100 feet of coax. =
> After some email exchanges with Tom, it appears that with at least 100 =
> feet of coax, I=E2=80=99ll be able to tune it with my internal tuner in =
> the ts-590, but with less than 100 feet I=E2=80=99ll need to use an =
> external tuner. He says that my MFJ tuner should tune the antenna with =
> 75 feet of coax. I=E2=80=99m not familiar with any coax length limits. =
> Can anyone explain why it=E2=80=99s necessary to have a long coax run to =
> this antenna? Also, I=E2=80=99m wondering what I should do with the =
> excess coax? Should I coil it some where, or just sort of spread it =
> out?
>
> Now it=E2=80=99s been years since I bought any coax. The last time I =
> did I got some 9913 50 ohm coax that had tinfoil shielding between the =
> brade and center conductor to protect the insulation from UV. =
> I=E2=80=99d welcome thoughts on recommended coax for 6 =E2=80=93 80 =
> meters.
> --
> Jim Shaffer, KE5AL
> Pflugerville, TX
> www.jjshaffer.net
> www.pgramblers.com
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