Found in Popular Electronics from the 90s, this circuit turns off an appliance at the end of the programmed time. The 12 V relay must have contacts according to the controlled current.
This configuration with the LM383 appears elsewhere on this site. The circuit shown was obtained...
This signal attenuator was suggested by Electronics Now magazine in April 1999. The circuit is...
The voltage gain of this DC amplifier is 100 times, given by the relationship between R2 and R1....