When the phone rings, you do not have to run to the next room just to answer it. With a cordless phone, you can walk around your house, office, or garden while talking to your friend or client. You can carry the phone anywhere, as long as you stay within signal range.

The cordless phone combines two technologies: telephone and radio. The unit transmits and receives signals.

There are two major parts to a cordless phone. It has a base connected to the telephone wire connection. It is responsible for receiving signals that are transformed into electrical signals. The electrical signals are converted by the base into an FM radio signal. The second part, on the other hand, is the handset which the user carries around. This is the part of the device that receives the FM radio signal broadcasted by the base. The radio signal is then transformed into an electronic signal, which in turn, is converted into sound as it passes though the phone speaker.

The same process happens when the user talks into the mouthpiece. A second FM radio signal is sent out to the base. The base does the reverse of the process to send it to the caller's phone unit. This capability is made possible by what is called the duplex frequency. Two sets of FM radios and electronic signals are transmitted to the same devices at the same time.

But because you are dealing with radio signals here, there is always the risk of other people picking up your signals through radio scanning devices. People can also steal your phone line and rack up expensive telephone calls. All a person needs to do is bring his cordless phone near your house. If you have compatible phones and have not activated your password protection protocol, the person can go right ahead and make calls on your behalf, without you knowing it.