This timing circuit was found in old documentation. The technology is CMOS. The supply can be made with voltages from 3 to 12 V. The time depends on R1 and C1.
This circuit is from a 1998 Poptronics. The circuit triggers a buzzer after a certain time, waking...
An integrated circuit 741 (operational amplifier is the basis of this voltage indicator, which can also...
This transistorized voltage converter is one of the oldest that we find in technical publications. It...