ABSTRACT
Analog multipliers are used to get voltage-tunable active filters. An analog multiplier as a non-linear network element is realizing the transfer characteristics active filters. Tunable active filters are adjusted manually using potentiometers. Electronic tuning provides for automatic adjustment and such tuning can be accomplished with analog multipliers in active filters. A change in the effective time constant can be achieved. With this ability to control time constants, very rapid adjustments to filter characteristics can be made by varying the control voltages on multiplier input. Modulation and frequency doubling are basically processes of multiplication. Balanced modulators are widely used in communication systems, measurements and instrumentation, and control systems. They have the advantage over other modulation schemes that the carrier is suppressed and does not appear in the output, and hence power consumption is reduced.
