I'm born in 1962, I was 17, and it was my first professional design project. The goal was to replace a relay-based control, with lamps and buttons.
It consisted of a discrete SR flip-flop with 2 transistors, one logic SCR to latch the alarm condition, and a five or six input diode Or-gate, with an independent LED on each input for the alarms (missing bag, over-pressure, door open...)
The multi-LED indicator was a significant improvement because in the relay-based version it was a nightmare to guess "what's wrong".
I continued manufacturing those boards for almost 3 yrs. from 1979 to 1982, in Buenos Aires, Argentina. Sorry, but I have no idea if I still have a picture because I moved from Argentina to Spain in 2002.
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