Old AC-Powered Fire Alarm Horns!

It's time to take a look at some more electromechanical fire alarm horns, from the era where many systems operated on 120 VAC instead of 24 VDC.

Featured in this video are the Edwards model 374 Adaptahorn, the deafeningly loud Faraday Type 512, and the rare and unusual Faraday 7410 reed buzzer.

Also shown are two Cerberus Pyrotronics model HAC-120 "Pyr-A-Larm" horns. These are relabeled Federal Signal Vibratone 350 DR horns. These horns differ from the normal 350 (aka the Simplex 4040) in the presence of a polarizing diode. I don't know what purpose this served, so feel free to leave a comment!

Table of Contents:
0:00 - Introduction
0:21 - Edwards 374 Adaptahorn overview
0:36 - Edwards 374 Adaptahorn - test
0:49 - Faraday Type 512 overview
1:05 - Faraday Type 512 test
1:15 - Faraday 7410 overview
1:30 - Faraday 7410 test
1:41 - Pyrotronics HAC-120 overview
1:58 - Pyrotronics HAC-120 test (Series A1)
2:04 - Pyrotronics HAC-120 test (Series B1)
2:15 - Science Lesson!
3:07 - Conclusion