We found this alarm circuit in a Radio Electronics magazine from July 1990. The power transistor must be equipped with a heat sink.
This circuit was found in a 2005 Linear Technology application manual. The circuit is for 48 V...
Using the 4001 integrated circuit, this latching relay can employ any general-purpose transistor. The...
This circuit with automatic gain control was found in the July 1988 issue of Radio Electronics magazine....