A new microwave (10 GHz) transmitter-receiver switch (T/R switch) whic
h uses high-T-c superconductive (HTS) film elements is presented. Its
operating principle is based on the fast switching of the film from th
e superconducting (S) state to the normal conducting (N) state under m
icrowave (MW) pulses. In the 20% band width, the device demonstrates d
ecoupling of >30dB between transmitter and receiver at 100W pulse powe
r. The transmission coefficient between transmitter and antenna is sim
ilar to 1.5dB and between antenna and receiver is <1dB.