A 2-outlet Alarm Receiver with a speaker

In 2005 we had a burglary, after which I installed a switch on the side gate. This communicated via X-10 modules with an alarm, the living room ceiling light, and to a digital recorder, which is now part of the Weather station.
This served until 2016 when the buried cable failed which connects the gate switch. I then made an RF transmitter for the gate. This provided an alarm on the Portable Receiver and recording on the Weather Station. These only required software modifications. For the living room ceiling light I pressed into service the Outside Receiver, which was originally made to control outside Christmas lights. An additional unit with a piezo annunciator was hard-wired to the receiver. This mess is pictured on the right
This project replaces all of that with a self-contained box, which originally contained a DVD drive with SCSI interfaces. It conveniently retains a 5 and 12 V switching power supply and a quiet 12 V fan. An oval speaker is behind the drive opening, and a household dual receptacle fits neatly into the SCSI cutouts.

Here are the circuit diagrams

Here is the code

This is the old alarm setup using the Outside Receiver

The ceiling light plugs into it. The unit is programmed to light the ceiling light when the gate is open.The light can also be controlled by a transmitter separately..The two outlets are split, providing an additional control. The inside view of the chassis shows that the RF receiver is mounted to the rear panel because the cabinet is shielded. Also on the back panel are the two power relays, to keep line voltage away from the electronics, which is all on a plug-in board.

This is the chassis. It slides into the cabinet from its rear. The circuit board fits into a slot and plugs into the receiver, power supply and relay board with a 16-pin connector.
The speaker and the fan have their own connectors.