The General Second-Order Twin-T and Its Application to Frequency-Emphasizing Networks

The twin-T as represented in Fig. 1 consists of the three resistors Ri , R2 , R:i and the three capacitors Ct , C2 , C3 . A straightforward analysis provides its F-matrix as as3 + sb + /) + s(c + g) + 1 Y = R.(R,C3S + 1 )(R3C.s + 1) as3 + bs2 + cs + 1 R.(RpC3s + 1 )(R3C.S + 1) as3 + bs' + cs + 1 R,(R,,C3S + l)(R3C,s + 1) as + sJ(b + d) + s(c + e) + 1 R,(R,,C3S + 1 )(R3C,S + 1) (la) 301 302 THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1972 Fig. 1--The twin-T.