Sounds like you are on the right track, and while it's nice to have a good 
tuner in the station, it's  better to have the antenna properly  installed 
and adjusted.

The 75 ohm matching line needs to be there for 20 meters.  It needs to be at 
the antenna  and not at the radio end.   Length depends on the  type of coax 
used.  You can use a pl 258 double female to connect the pl 259 male of your 
50 ohm coax to the pl 259 male of the 75 ohm coax.  The Wireman in SC 
www.thewireman.com sells this line for $18 and has a pl 259 on the antenna 
end and a female uhf connector  to connect direct to the pl 259 of the 50 
ohm coax, without using a double female.

Here is a bit from the butternut troubleshooting guide:

Symptom: High SWR on 20 meter; other bands OK.

Look for: Missing matching line. Antenna not properly tuned. 20 meter 
radials not present or
wrong length. Consult instructions for tuning and radial information; 
install
matching line RG-11 75 ohm coax, 11 ft 4 in (345.4 cm) if solid dielectric, 
13 ft 6 in

(411.5 cm) if foam type.


73, Steve KW3A

----- Original Message ----- 
From: "Gery Gaubert" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, June 29, 2007 10:42 PM
Subject: good news


> Well tomorrow is the day.  My dad is coming over to help move the
> vertical and also bringing a 20 meter dipole.  I'll be on the air
> tomorrow night, at least I hope so.  I also am strongly considering the
> ldg z100 tuner, maybe it will help some.  I am working on an alternate
> place to put the vertical away from the fence and house.  To do this I
> will probably have a run of about 100 to 150 feet of coax.  I'll
> experiment and see what happens.   Sorry for being long winded but I
> also read in the butternut manual and heard on this list too that a
> piece of 75 ohm coax needed to be included for 20 meters.  Is there a
> certain length and can I get a male and female connector to accomplish
> this?  Also, can the piece of 75 ohm line be connected to the radio and
> the 50 ohm be connected after that?
>
> Gery Gaubert
> St. Charles Sheriff's Office Helpdesk Coordinator
>
>
>