Audio intercom KNSP-04-D23

emergencyhelp pointfor railway applications

1. Product features Automatically dial with one button With LED light on the top as ringing indicator Send address code of this machine, and code sending time can be adjustable High waterproof, dustproof performance, full aluminum phone cover, IP66 protection grade.Sprayed with imported reflective lacquer on the surface, bright color, 5-10 years not fading, completely conform to the standards of GB/T5237.2-2000. 2. Scope of application It is applied to highway for emergency call, railway or subway for interval telephone call, and tunnels, electric tunnels for maintenance call. 3. Technical Parameters Ambient temperature:-30 ~ +60 degreeRelative humidity:10%~95% Atmospheric pressure: 86~106Kpa Circumstance noise:less than 60dB(A) Sound level of ringing:over 70dB(A). Standard frequency:low frequency group:697. 770. 852. 941Hz, high frequency group:1209. 1336. 1477Hz, frequency deviation:-1.5% ~ +1.5% If service line is a 3Km signal - level: Standard frequency:low frequency group:-12dB~-6dB, high frequency group:-10dB~-4dB, level difference between low and high frequency of compound signal:0dB~3dB, the total distortion caused by intermodulation of harmonic wave is lower than the basic level by at least 20dB. Call transmission index:(5KM)SLR<12,RLR10, output impedance is 600 Ohm Parameters is kept in EEPROM, no losing with power-fail.