This circuit activates a buzzer when the voltage applied to the input falls below a preset value in R1. The circuit is from an 80's American documentation.
We find this circuit in a 1994 technical documentation. The circuit has a 12 V input and a 33 V...
This transistorized oscillator was published in the July 1953 issue of Radio Electronics....
This circuit was obtained from a 1969 Electronic Design. Transistors admit modern equivalents. The frequency...