The FC-40 is a microprocessor-controlled antenna impedance matching network designed for use with all versions (original and āDā) of the FT-450, FT-857, and FT-897 HF/VHF/UHF Transceivers. The FC-40 makes use of control circuitry inside the transceiver, allowing the operator to monitor and control operation of the FC-40, which mounts near the antenna feedpoint.