S_2012122811380741YBThe AT-70 is a UHF antenna that stabilizes signal receiving and prevents impedance interference from nearby objects because its vertical 1/4 wave antenna is surrounded by horizontal antennas set at a 45° degree angle, causing a 1/2 wave dipole antenna effect. The AT-70 has higher positive gain than a 1/4 wave single rod antenna and smoother impedance within the 620 ~ 960 MHz band. Therefore, the length of the antenna does not need to be adjusted while receiving and the antenna is able to reduce interference by filtering signals outside the optimal range. Its 50 Ω impedance matches with regular 50 Ω impedance antenna cables. It is suggested it should be installed at the central location of a hall, on the wall, inverted on a ceiling, or mounted on a tripod (MS-30).