It is a radio transmitter that release FM (Frequency Modulated) signal most commonly between the ranges of 48,830 to 48,890 MHz. These devices have two components, the transmitter and the receiver. Transmitters are being placed 8-10 feet within the baby or closer if possible. Sounds coming from the baby are being picked up and a signal is then transmitted to the receiver. From time to time, their receivers are able to pick up signals from their neighbors' wireless devices baby monitors included. Because of these occurrences, a lot of people have made it a point not to mention any private or confidential information while the baby monitor is switched on. Interference with cordless phones and wireless routers is also a common problem. You can then carry the portable receiver around during the day or just leave it plugged in at the side of your bed at nighttime. These days, a good number of baby monitors are battery-operated. Some models even have extra capabilities including a video monitoring feature and an option that lets your baby hear your comforting voice. There are even some devices that will let you send commands to the baby s device to play different music to hush him or her back to sleep. Both types of baby monitors, audio and video, can either be wired or wireless. The wireless devices may, in some cases, be more advantageous than the wired devices since you will be able to go anywhere anytime for as long as both devices are within range. When examined by experts, these sounds can t be technically explained. But when examined by professional ghost hunters, they turn out to be ghost voices also known as electronic voice phenomenon. Baby Monitors and Interference Baby monitors can either be wired and wireless. Both types of devices have their own advantages and disadvantages. Another special feature that some video baby monitor provides is the baby cam feature. With the use of the Internet, parents will be able to keep track of their baby. A few simple clicks on the computer and the baby cam can be accessed anywhere and anytime. This is most useful for those parents who have to go to the office and leave the baby with a babysitter or nanny.