Good day.I served in the army in 1989. The company at the post of the supervisory was a gray box with two leds and buttons, red and yellow. The same were also on the staff, etc. Should go on some kind of signalling device, which raise an alarm sound continuously and the light and he was able to at the same time transmit a voice message. Does anyone know what system? I can't find any details, I just remember that it was called watchtower or something..