I used to get a solid 10mi connection base station to base station with a Shakespeare Big Stick 1/2 wave vertical, on a short 20' mast... almost 1 to 1 SWR and I think that having a 4' ground rod connected to the mast was a big part of the success... the radio was just a Cobra 21 with a Radio Shack 12v power supply (a variable would have given a couple of more volts)