This conventional filter circuit is from American documentation from the 1990s. The operational amplifier admits an equivalent and the power supply must be symmetrical.
This circuit was found in a Japanese documentation of the 70's. It uses transistors of the era and is...
The circuit shown in the figure is based on the ST Microelectronics TDEO0160 (www.st.com) and...
This lead-acid battery charger was found in a Popular Electronics from the 90s. The circuit has a...