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Old June 3rd 05, 08:53 PM
Fred W4JLE
 
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First, I would say that 1.7 to 1 is fine, leave it alone. It is what is
expected.

That being said, the strident need to be 1:1 can be met in several ways. The
antenna will probably be around 35 ohms. giving you the 1.7:1 you observe.
You can wind a toroid (t-106-2) with 14 turns of wire. tap one of the wires
at 11 turns and feed the antenna. A 50pf cap between the antenna and ground
might also prove usefull.

to wind the toroid, start with a black and white wire, wind 14 times through
the hole. Connect the black start end to the coax center. Connect the white
start to the black finish. Connect the white finish to the coax shield, and
vehicle ground. At turn 11 of the black wire, put a tap. This tap goes to
the antenna.

The SWR meter should now read 1:1 and you won't get out one bit better.

The SWR on my base feedlines are 9:1 by design. I run a screwdriver on the
car and once I am below 2:1, the radio is happy and so am I.



"wb5cys" wb5c ...
I put a mount on my Dodge pickup, bolted to the bed rail with 4 stainless
steel bolts. I placed a 20M Hamstick on the mount and the lowest I could

get
the SWR to drop at my desired frequency was 1.7 to 1. So I placed a small
matching coil at the base of the antenna (also made by the same

manufacturer
as the antenna). As I started trying to bring the SWR down I noticed that
anywhere that I touched the coil with the shorting wire would make the SWR
rise. At the very end of the coil - away from the mounting point, the rise
was minimal. As I moved the clip closer to the coil mounting point the SWR
rose.

The same thing happens with my 40M hamstick.

What does this tell me? Am I doing something incorrectly in the matching
process?

Thanks for any and all advice.

WB5CYS
Texas