http://www.infobarrel.com/The_Different_Types_of_Doorbells
published May 18, 2009
The Different Types of Doorbells
by PeterFalcon
There are many types of doorbells available in the market and the many different styles all do work in slightly different ways. The most basic models that are the traditional style of doorbell need a sounding system, push button and transformer. More advanced and wireless doorbells use a transmitter and receiver, and antique doorbells use a knob and bell. Transformers are needed for doorbells because the 110V from your electrical plug would burn out the doorbell, as they do not need that much voltage.
Antique doorbells are the easiest to install. These doorbells are popular for historic homes and function in the following way. When the knob is turned the bell on the inside sounds. The only installation that is needed may include drilling a hole through the wall so you can connect the outdoor knob to the indoor bell. There are no electric wires to deal with.
Intercom systems are also being used as doorbells. So you can have a conversation with the person at your door before letting them in. Intercoms are generally used for apartment buildings and are very secure.
Wired doorbells include some extensive wires in the wall as well as a transformer. Many times when your doorbell stops working it is because the transformer has worn down. The doorbell then acts like a circuit so that when the doorbell button is compressed the circuit is complete and produces a sound.
The most basic of chimes is produced from two flat bars that are just below two solenoids. The flat bars are tuned to produce a specific pitch when struck by the solenoids. You can have more then two bars as many bars and solenoids are used for doorbells that play short musical tunes.
The wireless doorbell is slowly becoming the upgrade of choice, as it involves no wiring at all. The doorbell button acts as a transmitter and sends the doorbell a receiver when someone pushes the button. The receiver will then play a sound to alert you that someone is at the door. There is some programming involved with t a wireless doorbell as many people like to play different songs depending on the door.