This simple timer for incandescent lamps or other non-electronic charges uses a triac as a control element. The triac must be mounted on a heatsink and the time obtained depends on capacitor C2.
This experimental TTL circuit is from 1992 documentation. It produces programmed sounds set in the...
This circuit is from a 1968 Electronic Design. The characteristics of the output transformer are not...
In the figure we have a circuit that fires from a positive pulse of short duration applied to its...