This filter was found in an American publication from the 1980s. The circuit can be implemented with any operational amplifier. The power supply must be symmetrical.
This radio's transistor is powered with the signal's own energy, producing its amplification....
Found in a 90s Electronic Design, this circuit can be used as a shield in current projects. The...
The integrated circuit used in this regulator is not very common today. The circuit is from old...