Specifications

Chapter 10 – SocketModem EDGE (MTSMC-E)
Multi-Tech Systems, Inc. Universal Socket Hardware Guide for Developers (S000342F) 137
Application Notes
Radio Characteristics
GSM 850 EGSM 900 GSM 1800 GSM 1900
Frequency RX
869 to 894 MHz 925 to 960 MHz 1805 to 1880 MHz 1930 to 1990 MHz
Frequency TX
824 to 849 MHz 880 to 915 MHz 1710 to 1785 MHz 1850 to 1910 MHz
RF Power Stand
2W at 12.5%
duty cycle
2W at 12.5% duty
cycle
1W at 12.5% duty
cycle
1W at 12.5% duty
cycle
Impedance 50 ohms
VSWR <2
Typical Radiated Gain 0 dBi on azimuth plane
Receiver Features
• EGSM Sensitivity : < -108 dBm
• GSM 1800/GSM 1900 Sensitivity : < -107 dBm
• Selectivity @ 200 kHz : > +9 dBc
• Selectivity @ 400 kHz : > +41 dBc
• Dynamic range : 62 dB
• Intermodulation : > -43 dBm
• Co-channel rejection : + 9 dBc
Transmitter Features
• Maximum output power (EGSM) : 24 dBm +/- 2 dB
• Maximum output power (DCS/PCS) : 30 dBm +/- 2 dB
• Minimum output power (EGSM): 5 dBm +/- 5 dB
• Minimum output power (DCS/PCS): 0 dBm +/- 5 dB
• H2 level : < -30 dBm
• H3 level : < -30 dBm
• Noise in 925 - 935 MHz : < -67 dBm
• Noise in 935 - 960 MHz : < -79 dBm
• Noise in 1805 - 1880 MHz : < -71 dBm
• Phase error at peak power : < 5 ° RMS
• Frequency error : +/- 0.1 ppm max
Audio Interface – Electrical Characteristics
Speaker Output
Differential speaker output capable of driving 8 ohm load. 1.0945 Vpp (differential) typical.
Microphone Input
Balanced microphone input: full scale input 1.1 Vpp.
Microphone Inputs
The MIC inputs are differential ones. They already include the convenient biasing for an electret microphone
(0,5 mA and 2 Volts). This electret microphone can be directly connected on these inputs. The impedance of
the microphone has to be around 2K. These inputs are the standard ones for a handset design.
The gain of the MIC inputs is internally adjusted. The gain can be tuned from 30dB to 51dB. The connection
to the microphone is direct.
MIC2N
MIC2P
C1
C1 = 22pF to 100 pF
33 pF recommended