I recently acquired a Simplex 4246-1 fire alarm panel! This panel came out of a church in Norwich, NY.
This panel is dated July 19th, 1969 and is now the oldest panel in my collection (previously held by my Gamewell Zans 200).
In addition to the panel, I also got some 4251-111 pull stations and a few 4040 horns (12 VAC @ 1.6A).
This panel is in excellent condition for its age, and based on the attached tag; I think this panel was in service until the end of 2022. Two interesting features of this 4246-1 are the auto-silence timer and the drill switch. I believe the auto-silence timer is configured at the factory; it automatically silences the horns after about 20-25 seconds. The drill switch is just a simple neat feature on the door: it’s essentially a manual evac switch.
Wiring up this panel is different than modern panels, particularly in adjusting the giant resistor at the top of the interior. This would be adjusted based on the voltage/current needed to power the horns on the gong circuit (NAC). The panel has one initiating zone: a Class A IDC. The initiating zone and the gong circuit are supervised. No internal buzzer, so the panel relied on a 120 VAC trouble bell instead. This is an awesome piece of fire alarm history that I’m glad I own!