Solari, from Udine in Italy, were indeed the pioneers of these boards. They are still in business using video displays nowadays.
The boards were driven by pre-prepared punched cards which an operator inserted and then operated a switch to send electronic pulses to each display.
There were two basic types, ones that did each individual letter of words (popular at airports) and ones that displayed the whole name at once (more common at train stations).
Downsides of the system were the need for a skilled full time punched card operator (and thus multiple shifts of them), and the sheer mechanical complexity that could absorb a technician full time to keep them going, as well as quite a comprehensive storeroom full of spare parts that had to be ordered and imported from Italy through Solari's local dealer. Although driven by electric motors they used a bicycle chain mechanism (actually lots of them) behind the boards to drive the displays, all of which needed oiling, jammed, broke their bicycle chains, showed nonsense, and sundry other misdemeanours. You needed a walkway space behind the large boards for a technician to access and work on them. They were also all custom designed and manufactured rather than just using standard IT screens, and therefore were a considerable cost to buy. The whole-name ones also needed updating with new words from time to time, which meant you had to resequence the whole display.
The one installed at Waterloo railway station in London, a whole-word type, displayed at the bottom of a particular train, only if required, "Delayed"/"Cancelled", then "due to", and then a whole series of excuses, which you saw momentarily when it was cycling round - "Staff Shortage"/"Late incoming train"/"Bad weather"/"Snow"/"Signal Failure"/"Vandalism", etc, it was an extensive and hilarious series of justifications.
Last edited by WHBM; 10th Aug 2012 at 21:56.