This configuration makes use of currently uncommon components. In fact, we found it in documentation from the 70s. Equivalent operational amplifiers can be used.
Originally this circuit was indicated to be used in a garage door control, but it can be modified for...
This conventional oscillator with the 741 can be precisely adjusted to produce a 400 Hz signal. The...
This current-limited circuit was found in a Popular Electronics from the 90's. ...