This is a simple - easy to build - latching relay circuit
This is a photograph of the Untimed Output Module. After the siren output switches off - this module will continue to supply power to other devices. You may want to use it to power a strobe light or an internal siren. If you connect a suitable relay to the module's output terminals - you can use the relay contacts to control anything you like - such as internal or external lighting. You can add as many of these Modules as you like to the One Time Only Alarm.
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