The Detroit News. A prototype of the alarm device was briefly tried at Engine 42's quarters at Chicago and Livernois in March 1992. The alarm, controlled by central dispatchers, would have alerted firefighters to emergencies with flashing lights and ringing bells, as is done in most fire departments. Most firehouses have devised their own alert systems, some as crude as the sound of a falling metal pipe.
Stations place the pipe on paper that feeds into a printer.
As the paper moves when a run notice comes across, the pipe rolls off and hits the floor, making a loud ping that alerts firefighters. Like anything new, the system had a few minor bugs but worked just fine. Wallcomm owner David Waller said he is still willing to manufacture the 55 alarm boxes the city originally planned to purchase. But, he said, he will only give up his right to patent the device if the city pays him a fair price for his invention and assumes all liability for the product. But there is currently a system that requires a firefighter stand on guard around the clock and monitor the printer for dispatch notices.