How a Baby Monitor Works

Audio baby monitors are actually radio transmitters. When there is a sound in baby's room, the monitor sends a signal to the receiver. As long as the receiver is within range, it picks up the sounds. There are two basic types of audio baby monitors - analog and digital, both types of monitors transmit the sound from baby's room to the receiver, but what is the difference?

Analog audio baby monitors operate on radio frequency that transmits a FM signal while the monitor is on. Most use a fixed frequency of 49MHz, 900MHz, or 2.4GHz. Your receiver will pick up this signal, but so will other receivers that are operating on the same bandwidth.

It is possible that your neighbor's baby monitor receiver will pick up your monitor's signal. It is possible to hear CB radio calls, cordless phone, and cell phone conversations through your receiver. If you can hear others, they may hear you. To minimize the problem, turn off the monitor when you are not monitoring baby. If your house has aluminum siding your signal is somewhat less apt to be picked up by other receivers.

Digital audio baby monitor signals provide more privacy. Digital monitors scramble the signal before transmitting to the receiver where the signal is then unscrambled. It is more difficult for another receiver to pick up a scrambled signal. Digital monitors have a larger reception range than analog, some advertising up to 2000 feet. Another plus is that digital models have less static and less interference from your other household electronics. Before purchasing a digital monitor, make sure it has digital technology and not just digital sound.

Whether the monitor has wireless capability or not has no bearing on the privacy of the transmission. In baby monitors, wireless equates to battery operation, not the use of a router like a wireless internet connection.