TCM1-83X+ Surface-Mount RF Transformer Mini-Circuits TCM1-83X+ Surface-Mount RF Transformer features an ultra-wide bandwidth of 10MHz to 8000MHz and a 30mA DC current rating. One TC1-83X+ model covers all telecommunication bands and offers flat insertion loss and good return loss. Mini-Circuits TCM1-83X+ Surface-Mount RF Transformer is ideal for wideband push-pull amplifiers, differential modulators, and LTE, Cellular, and Wi-Fi® applications.