This sounds like smoke and mirrors to me.  Depending on the frequency, the 
losses in a longer piece of coax will reduce the high SWR at the feed point 
to a level that your tuner can accommodate.  I can't think of any other 
explanation for such nonsense.  I would try it with a shorter run, 
lower-loss coax, or a remote tuner at the antenna feed-point.  I hope it 
works well.  I assume you have read reviews on E-Ham or something to back up 
the manufacturer's claims.  Unless the coax is expected to be part of the 
radiating section of the antenna, you could probably coil it up in the 
shack.
73 --


Lloyd Rasmussen, W3IUU, Kensington, MD
http://lras.home.sprynet.com
-----Original Message----- 
From: Jim Shaffer
Sent: Saturday, January 25, 2014 9:39 AM
To: [log in to unmask]
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