Zapper relay

Families who have child-proofed their audio and video equipment by hiding it
in a cabinet can now control it with their infrared handsets without even
opening the doors. The £30 Stereocontrol unit sits outside the cabinet,
where it can receive infrared signals from a remote control. The signals are
converted into electrical pulses, which are fed down thin wires to the equipment
inside, relaying the signals from the zapper.