Tom, I do believe your problem lies in the way you have mounted your ATAS120. Like all vertical antennas, the ATAS requires a very good ground plane to work against. The physical antenna is only one half of the actual antenna, the other half is the image created by the ground currents flowing the ground it works against. A large metal surface is best, but a length of metal pipe is also good. If it is mounted on the end of a PVC pipe and only connected to the MH chasis/ladder via a small wire that will not suffice as an RF ground. The wire has too much inductance. The wire may provide the DC necessary DC ground but the RF ground will be lacking. I have my ATAS120 also mounted to the MH ladder at the top. But I used a heavy metal clamp type mount right to the ladder and then grounded the lower end of the ladder to the MH frame using heavy 1 inch wide braid. It works fine with my FT100D. Mike NA9Q
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