a freind of mine is bleeding into his neighbers tv we ordered a hp1 from vectronics and installed it on there tv helped very little so we changed coax put all new coax and moved the antenna and got the antenna higher 50ft!!, with still no difference so my question is deos anybody out there make high pass filters that can go right to the antenna or hook straight to the back of an amplifier or something cause hes already spent a lot of extra money trying to solve this issue with no prevail and i am all out of info to help him!!!!!!!! he wanted to go with low pass but i told him there only good forgetting rid of interference comeing into the antenna system i hope i told him right!!!!