High pass and low pass filters
Subsonic and ultrasonic filters can be combined into a single circuit for more stable and orderly bandwith. This good and qualified for only two frequencies with the rotation of widely separate. Circuit schematic above shows the rotation of the scond-order or high-pass Butterworth filter in combination with secon-order low-pass filter. Part List : R1___1K R2___1K R3___12K R4___24K C1___4n4 C2___2n2 C3___470nF C4___470nF IC___IC op-amp For the capacitor , use the ceramic capacitors .