A switchable filter and diplexer circuit includes a plurality of bandpass filters having passbands for the frequency bands in which communication across a communication channel is desired and a plurality of diplexers, the diplexers having a plurality of passbands. A plurality of switches are provided to select one of the bandpass filters or diplexers from among the plurality of bandpass filters and diplexers for communication on a communication channel. An additional switching capability is provided to select a first passband of a given diplexer when a second passband of that diplexer is selected by the plurality of switches.