US Patent 7187285 System to detect mail in a mailbox

In a first embodiment, the system 10 includes a sensor 12, a transmitter 14 coupled to the sensor 12 and adapted to transmit a signal, a receiver 16 adapted to receive the signal, and a remote indicator 18 coupled to the receiver 16. In a second embodiment, the receivers 16′ are actually transceivers that can retransmit the signals to a receiver 16′ of another remote indicator 18 and that cooperatively form a mesh network. This arrangement may be quite useful in certain environments, such as a tall apartment building and a long private street, where multiple users are relatively spread out.