Burglar Alarm

The basic task of any burglar alarm is to keep people who should be in your home outside. Intruders can come in from many different places such as doors or windows. What if we could make something that would alert us when a door or window had been opened, effectively making us secure?

So here is the main question at hand, how can the average person make such a device?

The answer…its really simple, cheap, and effective!

All you have to do is use a simple circuit that will set off an alarm when it has been shut off with a switch. The best part is the switch is just a household clothes peg!

First things first – materials:

• A 9V battery (the correct scientific term is a cell)
• A 9V battery (cell) holder
• 2 thumb-tacks
• Approximately a meter of flexi-wire
• Electrical insulation tape
• An small electric buzzer
• A wooden clothes peg
• A sharp knife

And this is how you do it -

• Using a sharp knife, strip approximately 1 cm of the insulation off each end of the flexi-wire.
• Take both wires on one end of the flexi-wire and then connect them to the battery holder using insulation tape.
• Using the same method you used with the battery holding, attach the buzzer to the other end. If the buzzer makes a noise when you attached it then you know your construction is correct so far.
• Go about half way down one of the wires in two. You must leave the other wire alone. Strip the ends, leaving one centimeter unprotected.
• Now take the ends of the wires and place them in the mouth of the clothes peg. You will then need to press the thumb-tacks into the clothes pegs, securing the wires.
• Now it is time to attach the battery. If you close the clothes pegs the buzzer should sound. If it does not then you need to check all connections and try again.
• Once your system is in working order it is time to install it. Open the clothes peg and put it in the gap between the door and the door frame.
• If the door opens and the alarm sounds then you have caught your very first their. Take a moment and bask in the glory of your engineering achievement.

And there you have it – a simple and effective security system burglar alarm. You could replicate this experiment to protect your whole house if you so choose.

You can think of a burglar alarm as your homes personal bodyguard. It is working from the time you go to sleep to the time you wake up and start your day.  While the role of a home security might seem simple, that does not mean there is a lack of different types of devices.

Burglar alarms systems can be anything from a tiny little box that makes noise when it is tripped to an uber-complex unit with many tones and visual indicators. Of course, this would also be including alarms of the portable variety, namely those that are found in cars and tucks.

In order to make a decision about which alarm system is right for you, you must first attain basic knowledge about your different options. The first basic similarity between all alarm devices is that they contain a trigger that goes off when a home invader is detected.

Alarms can be broken down into two distinct parts, those that are set  off when the circuit is broken, and those that are set off when a motion sensor is compromised.

The two main types

The following explains the differences between the two main types of alarm devices:

Electric Circuit – These are what you would probably recognize as a simple alarm. They consist of wires that run along the outskirts of your home for protection. From here, you can separate security systems into two more sub-categories:

a) Closed-circuit systems – If your doors stay closed then the circuit is complete. However, if one of your doors was to open while the system is armed then the alarm would go off.

b) Open-circuit systems – This is the exact opposite of the above. When a door is opened the open-circuit is then completed and the alarm sounds.

Motion Detectors – These detectors work by detecting burglars via the use of radio signals that reflect back information to the terminal. If a person is to interfere with these radio signals, by walking in front of them, the alarm sounds.

So how exactly do they work?

Well, the terminal is connected  to sensors, either through radio signals or with an actual wire, and then the data gathered from the  sensors is sent back…which then signals the alarm.

Alarms are so sophisticated these days that they can distinguish the difference between changes in things such as temperature. When it really comes down to it you must decide what it is that you really need. Security systems, like many other products, are best decided upon based on consumer needs.