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Silent emergency alarm system for schools and the like
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Read, W. S. |
| Copyright Year | 1973 |
| Description | An emergency alert system is described. In a school each classroom (or other area) is instrumented with a hidden microphone and receiver tuned to a non-audible frequency. The receivers' outputs are connected to a central display unit in the school's administrative office. Each instructor is provided with a small concealable transmitter which, when hand activated by the instructor upon the occurrance of any emergency, generates a non-audible signal at the receiver's tuned frequency. |
| File Size | 594417 |
| Page Count | 9 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19730021473 |
| Archival Resource Key | ark:/13960/t5hb3wm45 |
| Language | English |
| Publisher Date | 1973-07-31 |
| Access Restriction | Open |
| Subject Keyword | Electronics Emergencies Wireless Communication Transmitter Receivers Subaudible Frequencies Warning Systems Schools Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Patent |
