Street map and advertisement display panel - has photoresistances associated with respective publicity spaces controlling map indication lights

摘要

The street map display panel has a central zone incorporating the street map surrounded by a number of reserved spaces which are used to publicise local businesses. Each of these spaces has an associated photoresistance which controls a respective light element incorporated at a given location on the map display, for allowing the light to be energised when the light falling on the photoresistance is blocked, or when the light fails due to night falling. Pref. the photoresistance are coupled to individual control circuits fed from a common supply source, e.g. using a number of photocells. The appts. is provided with an impedance circuit which raises the voltage if the output from one of the photocells is too short.