
This invention provides the novel dielectric BiCu.sub.3 Ti.sub.3 FeO.sub.12. BiCu.sub.3 Ti.sub.3 FeO.sub.12 provides good dielectric tunability and low loss over a frequency range of from 10 kHz to 10 MHz and is especially useful in tunable devices such as phase shifters, matching networks, oscillators, filters, resonators, and antennas comprising interdigital and trilayer capacitors, coplanar waveguides and microstrips.











