The Siemens MC35i Terminal Board is a robust unit with integrated GPRS and Dual-Band GSM functionality. It allows your project to utilise the full benefits of GPRS technology, such as permanent online connections plus cost-efficient, high-speed data transmission.
The ultra compact Dual-Band MC35i Terminal has all the right industrial interfaces for GPRS class 8 data, voice, SMS and fax applications. It can be powered by a wide range of voltages. A built-in SIM card reader makes it easy to plug the MC35i Terminal into your applications.
Group 3, class 1, 2
Power
The MC35 terminal is poweed via an RJ-12 Plug readily available form RS components or CPC or Farnell. Only 3 of the 6 RJ-12 pins are used. VDD: (8 to 30 V) Pin 1 and 4. GND: Pin 6
The board maybe powered from 8-30V DC. Current requirments vary depending upon the voltage supplied. @12VDC the board requires 200mA whereas at 24VDC the current required reduced to 100mA
It maybe that an RJ12 plug is not easily located, RJ-11 plugs (i.e. phone plugs), on the other hand, are really common and cheap but lack the external pins 1 and 6 (they only have the four central pins). A quick and dirty solution to allow the use of a RJ11 telephone plug is to make a link on the modem board, to connect pins 1 and 2 together and 5-6 together. You will be able to use a common RJ-11 jack and connect VDD to 1,3 pins (referred to 4 RJ-11 pinout) and GND to pin 4.
Serial communication
Communication with the MC35 is achieved with a standard RS-232 DB9 connector. The modem will respond to standard AT command set plus a set of dedicated AT commands. You may download the AT reference manual for MC35 terminal via this web page.
Antenna
When working with the modem, always have the antenna connected. Ensure that the antenna is suitable for the frequency bands in use, - a wet string or short peice of wire is NOT a good solution. The modem will respond poorly ( slowly or not at all) if it does not have valid signal.
SIM Card
When working with the modem, always have a valid and operable SIM card inserted. The modem will respond poorly ( slowly or not at all) if it does not have valid signal.