We found this active crossover in a Radio Electronics magazine from June 1961. Note the different adjustment ranges. The signal must be applied to the amplifier input.
This amplifier with differential input uses two old op amps but can be implemented with modern op amps....
The main feature of this circuit is that it provides a sine waveform signal. In this circuit, the...
The HA2620 integrated circuit used in this comparator is from the 80's, but the setting can be...