AT-70 is an UHF antenna that stabilizes signal receiving and prevents impedance interference from nearby objects because of its vertical 1/4 wave antenna is surround by horizontal antennas at a 45° degree, causing a 1/2 wave dipole antenna effect. Thus AT-70 has higher positive gain than a 1/4 wave single rod antenna and smoother impedance within 620 - 960 MHz band. Therefore, the length of the antenna does not need to be adjusted while receiving. The antenna is able to reduce interference by filtering signals outside the range. Its 50 O impedance for matching with regular 50 O impedance antenna cables.