Bests & Worsts Reviews from Amazon

Unit was set up as directed. I found that on the high setting the unit had a "buzzing" sound which was annoying, I tried it anyways. We spent 3 days with Tone only practice, I found that the tone was very inconsistent but being radio transmitted I figured there was a margin of error. Today we tried a low impulse. Although I could hear the tone the dog did not seem to react. We progressed through 2 and onto 3 (her coat is not very long and she's a thin dog). On three we went to the boundary and although I could hear the tone the dog did not react. I brought her back in the safe area, approximately 15' away from the boundary and she began to yelp and I could hear the impulses and no tone. I've asked for an exchange, maybe a defective unit. I'll post again when I get the new one.