Air TV channels transmit on frequencies ranging from 170 MHz to 860 MHz. The VHF-Hi band covers 175 to 230 MHz, while UHF covers 470 to 860 MHz. The gap between is used for cable TV. Receiving all these frequencies is difficult when using a single antenna.
The Gray-Hoverman antenna has been designed by Doyt R. Hoverman and it was patented in the All dimensions are in milimeters. The antenna can be built with aluminium or copper of 3 to 8 mm diameter.