This circuit was obtained from a Radio Electronics from the 90's. The circuit limits the strength of an audio signal preventing saturation. Equivalent operational amplifiers can be tried.
This circuit for link or alarm was found in the Encyclopedia of Electronic Circuits Volume 5 of...
This circuit is from a Popular Electronics of the 90's. Any power MOSFET can be used. The circuit...
This circuit extends the scale of a milliammeter. We found it in a documentation from the 60's. The...