Acquired a new site,but due to the weather I had to wait till today to detect on one of the fields, as soon as I started to detect in coin and jewellery,it started to pop and become very unstable,lowered the rx gain down to 2 still unstable ,thinking there was a major problem with my V3,as I started to walk back to my Nissan 4x4,the farmer came across the field and asked me had I found any thing I explained my detector was not working as it should ,he said I wonder if the phone mast had anything to do with it ,I looked bemused at him and said what mast ,he laughed and pointed to a tree not 30 yds away,man made he said, to hide the fact it was a phone mast,moving to another part of the field the V3 worked perfectly,relief was the order of the day,so in future I will be more aware of my surroundings .