This circuit rejects frequencies around 1 kHz and can be adjusted using C1. Equivalent operational amplifiers can be used, and the power supply must be symmetrical.
This circuit is from an English publication of 1982. The bipolar transistor can be a BC548 and the...
This circuit sequentially drives loads connected to its outputs or even applies the signals to the...
This low-pass filter was found in Intersil documentation from the 1980s. The circuit makes use of...