Help! I would appreciate thoughts on TV antenna’s and antenna principles. After the digital change over I’ve lost several channels. A couple of channels come in sometimes pretty good, but with continuous minor annoying breakups. I would like to understand a few principles before I attack in ignorance. My understanding is that all digital transmission is via UHF, which is the smaller portion usually on the tail of a standard antenna. Does the VHF portion serve any purpose now other than maybe AM radio reception? And can it be removed it as it causes interference with other structures limiting antenna rotation? How much help would raising the antenna provide? How does the signal strength usually vary with height? The antenna is currently about 20 ft. or so above the ground, but only about even with the peak of the second story roof, which is in the direction the broadcast is coming from and also metal tile. Thanks for any help anyone can provide.