Summary: | The first type of active RC networks referred to in the title use operational amplifiers, and the second use negative-impedance converters (NICs). Five networks using operational amplifiers, of which two are new, are found to be special cases of the same general network. They all realize a transfer function using single inversion. They are compared (1) Experimentally (all realizing a fourth order function). (2) Theoretically (second order function) with respect to (a) sensitivity to all passive components varying simultaneously (an appropriate sensitivity measure is introduced), (b) sensitivity to an arrangement they employ to produce -1 voltage gain, (c) the error introduced by the finite gain of the operational amplifier. One of the networks using two operational amplifiers, which is particularly suitable for the realization of any fourth order function, is found to be superior to all the others. An equivalent circuit of an uncompensated (non-ideal) NIC is introduced. Two well known synthesis procedures, those of Linvill and Yanagisawa, are extended, subject to a definite restriction, to use non-ideal NICs; the procedures are verified experimentally by realizing high-Q second order functions and the fourth order Bessel delay function. The sensitivity of four high-Q networks suitable for use with non-ideal NIC is studied and some useful properties of these networks discussed.
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