This circuit from a Popular Electronics from the 90s uses a common optocoupler and a general-purpose transistor to control a sensitive relay that can be from 6 to 12 V.
This circuit was found in a General Electric documentation from 1965. The circuit is full wave for...
We found this circuit in the Texas Instruments' Linear Circuits Applications. It uses an...
In the presented circuit it is possible to vary the frequency of the rectangular signal produced. This...