Patent ID: 9443416
Filing Date: 2016-09-13
CPC Classification: G08B

Claim Text:
1. A fire alarm system, in a structure having a pair of commercial power source conductors, said structure not fully wired with a dedicated alarm conductor, said fire alarm system comprising: an alarm; said alarm having an alarm conductor; an interface ( said interface having two power output conductors; said interface installed by: a second interface, similarly installed between a second alarm and said commercial power source conductors; each interface having: a circuit ( a pair of interface power input lines ( enter the circuit ( a power line interface ( a collision protector ( a receiver interface ( a band limited amplifier ( a sharp band pass filter ( a band limited amplifier ( a discriminator comparator ( a noise eliminating microcomputer ( the drive enable ( the output drive ( a power amplifier ( a band filter ( an impedance matching transformer ( a power-line interface (