Baby monitors have infiltrated most neighborhoods. If your neighborhood has even a few houses chances are you'll to hear one of these. Baby monitors, first marketed by Fischer Price are actually two devices, a transmitter usually placed in the baby's room and the receiver that Mom or Dad can carry around the house. Given the receiver they use, the systems range is typically limited to a few hundred feet. Using your scanner as the receiver, these can often be heard for several blocks especially when an outdoor antenna is used. After baby is asleep and the ambient noise level decreases, the transmitter's auto gain control often substantially increases the microphone sensitivity and monitors Mom and Dad! Note: Cordless telephones share these frequencies so you may not hear baby monitors on all channels

Cordless baby monitors can also be used as a scanner extender. The transmitter can be placed next to your scanner while the receiver can be taken pool side or out in the yard. After baby has grown up these can often be found at garage / tag sales for just a few dollars! 

Monitoring cordless phones is what most scanner listeners are noted for. By design they are low power devices and are designed to operate for only a few hundred feet. Like baby monitors, these can be heard for much greater distances if your scanned is connected to an outdoor antenna. If the phones base unit happens to be located on the upper floors of a multi-dwelling residence it's quite possible that they can be heard for distances of up to one half mile.

The telephones use two frequencies, typically in the 43-44 mhz, 46mhz and 49 mhz band. In order to hear both sides of the conversation you'll want to listen to the base unit whose frequencies are listed below.

Recently, cordless phones have started using frequencies between 902 - 928 Mhz. While some are "in the clear" and capable of being received, others used digital spread spectrum technology and cannot be monitored with equipment typically available to scanner hobbyists.

So called "scrambled cordless phones" often sound like single side band transmissions mimicking "Donald Duck." If you own a received capable of receiving SSB, try monitoring in the upper or lower side band modes and decrease the tuning increment to at least 100 hz. In most cases you will be able to tune these in! The annoying "whistle" can also be removed if your receiver has a DSP (Digital Signal Processor) circuit to remove a heterodyne.