This circuit was found in an Electronic Design from the 90's. It makes use of components from the time. Triac is according to the controlled load.
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...