This circuit was found in the April 1993 Electronics Now magazine. With it, it is possible to control the gain of an operational circuit with a JFET.
The critical components of this 1978 circuit are transformers, which, hopefully, can be obtained from...
This circuit was found in a 1995 documentation, consisting of a car protection system that blocks...
Suitable for dual applications, this timer was found in a 90s Popular Electronics. The circuit...