The proposed system is designed as a GSM based auto call receiver, that attends call automatically for configured numbers and call will be redirected to 64 different locations with zone numbers accepted as an extension. This system consists of 1 main unit with 7 zone expanders which can be connected to a maximum of 64 extensions. With each zone expanders, 7 local communicator can be connected which can be placed in particular location in the work place. The unit with GSM receives the call at the 3rd ring and prompts for entering the extension number by playing the pre-recorded voice message. After selecting the required number, the call is redirected to the desired location and it works as a two way communication unit with the help of inbuilt Microphone and Speaker.

All the local communicator (Receiver) unit is provided with intrusion alert system as an additional feature. It will play the prerecorded voice and enable the strobe light/hooter as an alert indication whenever the unit senses abnormal condition in that particular location. The abnormal condition is sensed by various sensors like PIR sensor, contact sensor, beam sensor, IP cameras alert etc. The pre recorded voice is terminated as soon as any call is connected from CMS to the unit. The system user can change the pre-recorded voice based on the requirement. User can also control the strobe light and hooter in local communicator unit by using the CMS. User can communicate to multiple locators with this system, but only one group of zones with 8 local units can be selected by the user at a time and establish communication, The user can switch between zone groups using CMS.


  • 12V DC supply input to the system.
  • Auto call attender with multichannel two way communication interface.
  • Maximum of 64 channels with 8 zone groups.
  •  Maximum group communication possible upto 8 Receiver unit.
  • TDA2009 speaker amplifier to amplify and send the output of GSM to       receiver cards.
  • Intrusion alert system in receiver units.
  • Receiver selection through CMS / Calling user.
  • Number of receiver and zone expander cards can be configured based on the requirement.
  • Pre-recorded voice for alert indication using SD card.
  •  Relay controlled receiver cards connected to main card.
  •  DTMF based Zone expander and Receiver cards selection and control.
  •  Modbus communication to select Zone expander and receiver cards.
  •  CMS controlled output relays in the receiver unit.

Specification Sheet
Specification Sheet
Specification Sheet
Specification Sheet
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