Type CATC is a medium gain collinear antennas suitable for masthead mounting or stand-off mounting from a tower or a mast. A high degree of decoupling from the support structure and the feeder cable is achieved without the use of groundplane rods. The radiating elements are encapsulated in low-loss polyurethane foam which bonds them firmly to the inside of the radiator housing thus ensuring good mechanical stability. The antenna is fitted with a short length of URM67 coaxial cable terminated is a type N series plug.