http://www.youtube.com/watch?v=-q2WgAep5K8 - (EXPLICIT LANGUAGE IN VIDEO AND DESCRIPTION) SpectrAlert Advance alarms in code-3.
http://www.youtube.com/watch?v=RIKutw-s0tc - (skip to 3:43) Smoke detector.
http://www.youtube.com/watch?v=1bzngXTNbzM - (skip to 1:41) Commander alarms in code-3 (unsynced horn).
http://www.youtube.com/watch?v=2AtiN0FduIc - Prankster pushes in on a call point station and sets off a 4" bell in continuous.
http://www.youtube.com/watch?v=bQ1eELmWyFQ - Hi-lo sounders and 6" bells in slow march time; a call point station can be seen towards the beginning.
http://www.youtube.com/watch?v=TIfXHI6Cxcc - (bad quality) See video description; signal coding is code-3 (unsynced horn).