... system,gsm pstn system,gsm pstn alarm system,gsm security system GSM and PSTN alarm system,gsm pstn system,gsm pstn alarm system,gsm security ... use. l Support dual-network of both PSTN landline and GSM mobile network, provide redundancy for extra stability. l Can ... , INTELLIGENT, EMERGENCY, CLOSED, HELP SENIOR, WELCOME and CHIME. l Four sets of scheduled arm/disarmed function, each time disarmed you ...