Stanley Tool STHT77587 0.75 in. Stud Finder

My wife bought this for me about 9 months ago and I just went to use it - lost my leg - now that I am moving around. I had lost the instructions as this thing was doing a lot of weird things so I came to this site to find instructions. Lo and behold, my Stud Finder is doing exactly what everybody else's is doing. I did a test on pony wall that had no electrical. It showed that there was electrical throughout, 1 stud and no studs at the ends. Totally unreliable.

What a junk of a device! According to this contraption, my whole wall has power cords inside it... all the time. I put it on my arm, even in me! The beep is so obnoxious, after 30 seconds I had such a headache I threw the piece of rubbish across the room. at least now there is a hole in the wall and I can SEE the studs, of which it could not find. Taking back to retailer THIS MORNING! Note: I had to edit this because I was not allowed to post the descriptive words I wanted to. Most of those words were similar to human waste.