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Product Description - GSM_WLL (Wireless Local Loop) + SMS

GSM_WLL + SMS is a GSM device which simulates the PSTN line. The device has a slot for GSM SIM card. The user would need to subscribe to a GSM phone number in order to use it. The device also has the Input/ Output pins to receive / send triggered signal and to send / receive SMS to / from up to five mobile phones. ( various views>>> )

One of the most popular applications would be to connect this device to the company PBX so that the Field Engineers or salesperson could use the same carrier when dialing to the main office and thus save on phone bills. The second major marketplace would be for residential PSTN phones to be replaced by the GSM_WLL + SMS so that family calls could also be through the same carrier to save on costs.

Figure 1: GSM_WLL+ SMS

General Features:
- Wireless Local Loop function
- SMS sending for the control of output devices and triggered event

Application Example Figure 1: FAE and Sales calls to the office using the same carrier to save on costs

Application Example Figure 2: Family and the house phones use the same carrier to save on costs

Application Example Figure 3: Door contact sensor open -> send SMS to up to five users

Application Example Figure 4: Send SMS to turn on/off lights or to open a door

   DC Jack for 6V
   RJ11 for analog phone or PBX
   6- pin terminal for 2 trigger in, 1 trigger out
   SIM card slot
   SMA connector for antenna
   5 LEDs for cellular signal strength
   One LED for GSM device
   One rotary switch for 16 stage MIC strength
   One rotary switch for 16 stage SPK strength


  • The GSM for GSM_WLL + SMS _3 is a Tri-Band while GSM_WLL + SMS _4 is a Quad-Band GSM/GPRS module.
  • Tri-Band GSM/GPRS 900/1800/1900 MHz or Quad-Band GSM/GPRS 850/900/1800/1900 MHz Low power consumption
  • Normal operation temperature: -20oC to +60oC
    Restricted operation temperature: -30 oC to -20 oC and +60 oC to +80 oC
    Storage temperature: -40oC to +85oC
  • RJ11 Specification:
    - Programmable Line impedance (default 600 ohm)
    - Programmable Ring generator (default 90Vpp /25Hz)
    - DTMF tone generate and decode
    - Line feed power DC 36V
    - Constant line feed current 20mA
  • SMS_2_IO Feature (Trigger in to send SMS and receiving SMS to send trigger out) :
    1). Support up to five mobile phones.
    2). One trigger out (Extendable)
    3). Two trigger in (Extendable)
    4). Send SMS to up to five mobile phones.
    5). Command for control: D or d : Device, Y or y : ON, N or n : OFF.
                   ex: dy1 (device 1 on),
                   ex: dn1dy2dy3(device 1 off, device 2 on, device 3 on).
    6). Command for setting the phone number: M or m
                   ex: M30952221362
                            M -> Setting the phone number
                            3 -> Set the 3rd phone number
                            0933940317 -> the phone number
    7). Send "OK" back to the original phone sending the command.
    8). Before setting the five mobile phone, GSM_WLL + SMS could receive SMS from any       phone to set up the parameters but not to control the IOs. After setting the phone       numbers, the device would only accept commands from these five phones except the       trigger out command. The trigger out command could be from any phone with a correct       password.
    9). Set up parameter through RS-232 for SMS_2_IO ->
          a: Setup five phone number,
          b: the particular phones to send the SMS upon triggered,
          c: Rename the name of the trigger in
          (Note: You would need to open the housing, use jumper at Jx and then use a level       converter for PC's RS232. After making these arrangements, you could then run       SMS_2_IOs Application Software)

*Specifications are subject to change without notice.


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