GSM / GPRS Modem - SIM900 - RS232

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  • Part No :
  • GSM-1933
  • Availability:
  • In Stock
  • Shipping :
  • Same Day
  • Weight:
  • 0.35Kg
  • Made By:
  • rhydoLABZ
  • Mfr.Part.No:
  • GSM-1933
  • Quality Rank:
  • 100/100
Rs 1999
(Tax Excl.)
Quantity :
Description: The SIM900 GSM/GPRS MODEM -RS232, from rhydoLABZ, is same as the GSM-1934 except that the DB9 Connector is replaced with an RMC connector. The Modem is built with Quad Band GSM/GPRS engine - SIM900, works on frequencies  850/ 900/ 1800/ 1900 MHz. The Modem has a RS232 interface, which allows you to connect PC as well as microcontroller with RS232 Chip(MAX232). The baud rate is configurable from 9600-115200 via AT commands. The GSM/GPRS Modem is having internal TCP/IP stack to enable you to connect with internet via GPRS. It is suitable for SMS, voice as well as DATA transfer application in M2M interface. SIM900 is a quad band modem, being able to operate in 850,900,1800,1900 MHz bands it is apt for world wide compliance.

The Modem is manufactured with Automatic Pick and place machine with high quality standard.The onboard Low dropout 3A Power supply allows you to connect wide range unregulated power supply  . Using this modem,you can make audio calls, SMS, Read SMS, attend the incoming calls and internet ect through simple AT commands.


Note: rhydoLABZ wiki has extensive contents
showing you how to get started, how to configure the GSM/GPRS Modem-RS232 Modem and other details such as pinout, schematic etc. Kindly visit our wiki page for any reference.

Modem Features:
  • High Quality Product (Not hobby grade)
  • Quad-Band GSM/GPRS  850/ 900/ 1800/ 1900 MHz 
  • RS232 interface @ RMC Connector for direct communication with computer or MCU kit
  • Configurable baud rate
  • SMA connector with GSM Antenna.
  • SIM Card holder.
  • Built in Network Status LED 
  • Inbuilt Powerful TCP/IP protocol stack for internet data transfer over GPRS.
  • Audio interface Connector
  • Normal operation temperature: -20 °C to +55 °C
  • Input Voltage: 5V-12V DC
SIM900 General Specification:
  • Quad-Band 850/ 900/ 1800/ 1900 MHz
  • GPRS multi-slot class 10/8
  • GPRS mobile station class B
  • Compliant to GSM phase 2/2+
    • Class 4 (2 W @ 900 MHz)
    • Class 1 (1 W @ 1800MHz)
  • Dimensions: 24x24x3mm
  • Weight: 3.4g
  • Control via AT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT Commands)
  • SIM application toolkit
  • Supply voltage range : 3.4V to 4.5V
  • Low power consumption: 1.0mA(sleep mode)
  • Operation temperature: -40°C to +85 °C
Modem Specifications:
  • Fax: Group 3, Class 1
  • Data
    • GPRS class 10: max. 85.6 kbps (downlink)
    • PBCCH support
    • Coding schemes CS 1, 2, 3, 4
    • CSD up to 14.4 kbps
    • USSD
    • Non transparent mode
    • PPP-stack
  • SMS
    • Point to point MO and MT
    • SMS cell broadcast
    • Text and PDU mode
  • Voice
    • Tricodec
      • Half rate (HR)
      • Full rate (FR)
      • Enhanced Full rate (EFR)
    • Hands-free operation (Echo suppression)
    • AMR
      • Half rate (HR)
      • Full rate (FR)
  • Firmware Support
    • FOTA
    • MMS
    • Java (cooperate with Iasolution)
    • Embedded AT
  • Other features
    • 0710 MUX protocol
    • Embedded TCP/UDP protocol
    • FTP/HTTP
  • Interfaces
    • Interface to external SIM 3V/ 1.8V
    • Analog audio interface
    • RTC backup
    • SPI interface (option)
    • Serial interface
    • Antenna pad
    • I2C
    • GPIO
    • PWM
    • ADC
  • Compatibility: AT cellular command interface
  • Certificates
    • CE
    • FCC
    • ROHS
    • PTCRB
    • GCF
    • IC
    • ICASA
    • REACH
Package Includes:
  • Fully Assembled and Tested GSM Modem with antenna.
  • 1x 2 Pin Female RMC connector (2mm)
  • 1x 4 Pin Female RMC connector (2mm)
  • 1x 5 Pin Female RMC connector (2mm)
Sort by: Recently  /  Helpful Write review

Works well

By Nithiya from Kollam, India on May 19, 2016
great easy to us product. serves the purpose well
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By Master Chief from N/A on January 07, 2016
I updated the onboard firmware as is working great. I recommend publishing a tutorial regarding firmware updation. This will be really helpful for those trying to make this happen.
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By Jamey Anderson from N/A on December 24, 2015
Your modems are compact and well designed, but why dont you have a USB revision for these?? Added with that it would be really great
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    • Q
    • Hi, Does it support DTMF via serial interace?

      asked by Prashantkumar R on July 19, 2016
    • A
    • Inbuilt DTMF decoder is present in SIM900 modems.But DTMF commands are not supported in all firmwares.SIM900 has released separate firmware (1137B08SIM900M64_ST_DTMF_JD_MMS) for implementing DTMF feature.

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GSM / GPRS Modem - SIM900 - RS232