There is no matching system at the base, and the antenna is pretty short.
The SWR should be higher than 3:1 except losses are involved. System loss
will tend to lower the SWR. The worse antenna efficiency becomes (within
limits), the lower SWR will become.
You could add a shunt capacitor from the feedpoint to ground (directly
across the coax) or an inductor across the coax. You probably are going to
need 35 ohms of capacitive or inductive reactance shunting the coax, and to
retune the antenna with that reactance there. That would be a 2400 pF
capacitor or a 3.1 uH inductor shunting the coax. The inductor would be
about 10 turns 2 inches in diameter, and might be easiest.
Then you just retune it to resonance.
----- Original Message -----
From: "Don" <w4dee@truvista.net>
To: <topband@contesting.com>
Sent: Saturday, January 17, 2015 8:49 PM
Subject: Topband: 160 VERT
I put up on of K6MM’s helically Wound 160 vert can not get SWR down
I put up k6mm Helically wound vert for 160 but can not get SWR below 3:1 I
have 8 - 1/4 wave radials of 16 awg wire out . Any suggestions you can
offer would be appreciated
W4DEE
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