Neighbours with a similar device Your neighbour may have a wireless or cordless device that transmits on the same frequency as yours. This could interfere with your receiver or pager, or stop it from working altogether. However, most use a coded radio signal. This means that your receiver or pager will respond only to the code from your device and you should not get interference from your neighbour's device. Most systems may also let you choose a different radio frequency by flicking a switch on your device or that of your neighbour's.
Wired devices are an alternative and sometimes cheaper option to wireless or cordless devices.
There are two types. The first type has to be wired into your home and communicates the alarm signal through the mains wiring. These have to be installed by a fully qualified electrician. The second type can simply be plugged into a mains socket. However, they also work by sending signals through your existing mains wiring.