If you want to get that repeater on the air in most cases you're going to need a duplexer. If you want to use a separate VHF and separate UHF antenna for instance with one radio you need a diplexer. If you want to split your signal into 3 antennas you need a triplexer. Diplexers and Triplexers also work in reverse. You can also use 2 radios with one dual-band antenna or 3 radios with one tri-band antenna! If you don't find what you need listed here please contact us for a free complete estimate.