This circuit is from American documentation from 1970. It can be designed with a BC558 and for the operational, we can use equivalents. The FET can be the BF245.
The circuit that we will see below uses an element of the semiconductor family that is not yet...
This circuit is from 1994, from a technical documentation from National Semiconductor, but can be...
This circuit is from a 1967 US publication. The configuration can serve as a basis for designs...