Abstract: A method and apparatus for causing a plurality of navigational lanterns, each equipped with an independent light sensing device and connected to a common synchronizing terminal, to actuate simultaneously at dusk, and deactuate simultaneously at dawn. The light sensing device senses the three levels of day, twilight and night. When a sensing device senses day, the connected lantern is disabled from flashing and is disabled from sending a synchronizing signal to other lanterns to flash. When a sensing device senses twilight, the connected lantern is enabled to receive the synchronizing signal, but is disabled from sending a synchronizing signal. When the sensing device senses night, the connecting lantern is enabled and a synchronizing signal to flash is sent to all of the lanterns.

Abstract: A lampchanger preferably for use in a railroad signal lantern having a focusing lens which includes a horizontally rotatable turret adapted to support a plurality of lamps for indexing one of the lamps to the focal point of the lens. The turret includes a plurality of bayonet sockets for holding a lamp in which the sockets have resilient sides which taper inwardly away from the turret body for accurately securing the lamp in position. The turret includes a contact insulator having a radially extending slot adjacent each of the sockets with a power contact positioned in each of the slots. Each power contact includes a circular ridge for engaging the bottom of a lamp positioned in a socket for cleaning and making a good contact with the lamp. A power brush engages the rotatable turret and is positioned to engage the power contact and engages the slot of the insulator positioned in lamp operating position for mechanically holding the turret in position.