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 source is used to supply circuits with operational amplifiers, being originally created for...
The transistors in this 80's documentation project may be BC548, the most modern equivalents of...
This circuit uses a FET to drive an LED with constante currente. The current up to 20 mA can be...