In this circuit found in a 1991 publication we can use the 2N2646 unijunction transistor and the triac can be any of the TIC series with current according to the controlled load. The Triac must be equipped with a heat radiator depending on the load. The circuit shuts off a load after the time determined by R7 and C3. See in the math section how to calculate these components for the desired times.
| Clique na imagem para ampliar |
