Old School Fire Alarm Technology

When I went to grade school in the 1960's and the Fire Alarm went off a very loud bell would sound and beat out a code where it had activated such as 2-2-1 or 2-2-3 and by counting the beats you knew which manual station had been activated. If your school had a really sophisticated system it would also have in the lobby a cabinet with a paper tape punch that would punch out that code to tell arriving firefighters exactly which station was activated. If it was a false alarm they would then have to go to the station with a key and open it up with a key usually shaped like a triangle on the end and rewind it and replace the breakable glass if it had this feature. the tape system also would have to be rewound. This was high tech fire alarm technology in the 60's .which some times these systems might have a mechanical heat detector and possibly a primitive photoelectric duct detector
But soon a modern revolution with electronics would evolve and things would change for ever how we would protect people. These old tape systems are all gone for the most part with only a couple still in use in buildings where systems have not been upgraded and will soon only be seen in museums. But wow it was something to see the systems operate back then what a technological achievement they where. On my Face Book page I have many different pictures of old Fire and Burglar alarms and your all welcome to look.