This is a light or beeping sound that lets you know that you've reached the monitor's range limit. If you have a model without this feature, static might be the only indication that you're out of range. (A monitor's range can vary due to your home's size, its construction materials, and other factors.) The greater the range, the better--especially if you plan to take your monitor outside.
Interchangeable Camera Lenses: Some of the newest baby monitors have interchangeable lenses to best suit your baby's room. If you have the camera positioned close to the baby, like on the edge of the crib or on a nearby dresser, you might prefer the wide angle camera. If you have the camera positioned relatively far from the baby, like on a bookshelf on the other side of the room, you might prefer the regular narrow angle camera. Flexibility is nice, particularly if you end up rearranging the room or have to move things out of the reach of a growing menace.
This monitor offers lots of convenient features. Don’t have the best view of your baby? Use the monitor to remotely pan, tilt or zoom the camera without having to go back into the nursery. Fussy baby? Press a button to play lullabies. Need the camera to move from your bedroom to the nursery? No problem: this freestanding monitor can be set on top of a dresser or grip onto shelves and brackets. You can also unplug it and use it in another room for up to three hours on a single charge. And there’s a room temperature display. But the most impressive feature is its 1,000-foot range—the highest of all cameras on this list. That means you can hear your little one’s every chirp even if you’re hanging out in your backyard.