Antenna Tuner
 

Hi
I have the MFJ 989C, and I am noticing that I can tune antenna to low SWR
but I also have noticed that the SWR often was jumping or spiking and very
unusual. I thought it may be coax or antenna or a short but then I noticed
also that the inductance coil is very sensitive. If you touch it or tap it
this will cause the SWR to spike. Also when it spikes, if you put a little
pressure on the Inductance coil knob it will solve the problem. Anyone else
have situation such as this? What did you do to fix the problem? I opened it
up and cleaned the contacts where I thought the problem was but still didn't
correct the problem.
Any ideas ???