I have a SteppIR model DB18 that I put up in mid-January. It's 3-elment 6-40 meters. Controller is an SDA 2000. It was
working great for two months until the SWR increased recently, increasing to the 1.5-2:00 range. For example, the best I can do on 20
meters is 1.98:1 . I use a RigExpert AA-55 antenna analyzer to sweep over the band plus a little more on each end. It's odd
that the SWR dip is usually around 500 kHz away. Clarifying that, I set the Controller to 14.500 and the best SWR is 1.98 at
14.020 on the analyzer. Setting the Controller to 14.600 results in the lowest SWR of 2.00 at 14.100. it was never like
that before.
I used to be able to get it down to 1:1 by using the SDA 2000 Controller to
tweak its frequency a little thus matching the antenna element lengths to the
transmit or analyzer freq.
It has rained recently, and that is a thought. But it rained several time before, and
even iced several times, without any impact.
I was very careful when building the antenna to securely wrap all of the connectors to
waterproof them,. The coax is new RG-213 purchased from DX Engineering.
Could it be the Controller, or some part of the coax/antenna combo?
Would appreciate your opinion to help me troubleshoot and solve the problem.
tnx es 73
Fred w3ICM
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