This filter has the components calculated for the frequency of 1 kHz but can be changed. The input resistor can be 100k and the source symmetrical. Any operational amplifier can be used.
We found this circuit in old American documentation. It can be implemented with more modern...
The purpose of this circuit is to control the high and low light of a car, detecting when a...
This powerful transmitter for the 27 MHz band was found in a Japanese publication from 1961. The...