Hmm. My homemade 20M Ground Plane antenna that was nicely resonant on 20M now has a 3:1 SWR on 20M but is 1:1 on 30M! Perhaps I should patent the design, how to make a resonant 30m vertical out of 17.5 feet of aluminium tubing! The other odd thing is that the SWR is only around 3:1 on 10M, 12M, and 15M. I would expect it to be much higher without tuner. It is not until I get to 40M that I get a very high SWR. I'll be going outside to check , when the weather clears. It will be interesting to find out what has happened
Andy K3UK
