In order to remotely detect intrusion into a particular room, a security system is needed. Many of them are difficult and expensive. But a very simple system can be made at home.
Instructions
Step 1
Take an old, unnecessary but functional mobile phone. Remove the battery and SIM card from it.
Step 2
Open the device using the specially designed screwdrivers. Do not use ordinary screwdrivers to avoid damaging the screw slots.
Step 3
Connect two wires to the call button. Take them out, for which make a recess in one of the walls of the case. Assemble your phone.
Step 4
Install the SIM card and battery into the device. Turn it on. Dial the number of another phone that also belongs to you, but do not press the call button.
Step 5
Short-circuit the wires leading out of the phone. Make sure your second phone is receiving an incoming call. Do not pick up the handset on it.
Step 6
Turn off all sounds in the phone's menu, including any service sounds, as well as the vibrating alert. Connect a reed switch to the outside wires, and attach a magnet to the door. Position the reed switch in such a way that, both when opening and closing, the magnet will quickly "fly" past it, causing a short circuit.
Step 7
Place the telephone inside the protected area in such a way that it does not interfere with the door opening and cannot be seen. Connect the charger included in the network to it. Dial the number of your second telephone on it again, but do not press the call button.
Step 8
Enter the number of the first in the memory of the second phone and name it "Alarm". If you answer the call, funds will be debited from the account of the first phone, but you will hear what is happening in the room.
Step 9
At least once every six months, use any paid service on the first phone, otherwise the SIM card will be blocked. Top up his account in time. Do not use home-made alarms to guard critical facilities. To do this, purchase a properly certified industrial fabrication system.
