GDI SM2400 Series 2400 bps Dialup Modem

GDI Smart Modem SM2400 SM2400 (170 Plug-in) SM2400SA (standalone)

GDI SM2400 Series 2400 bps Dialup Modem
1-301-924-7400 ext. 17


* Standard “AT” Command Set
* RS232 Interface
* Call Monitor Speaker
* Error Correction / Data Compression
* Integral Power Supply
* Rugged Metal Enclosure
* Wide Operating Temperature Range –37 to +74oC
* Standalone or 170 Plug-in Card



The GDI Smart Modem SM2400 is an AT command set compatible dial-up modem. This modem has been designed specifically for the demands of the traffic industry. The GDI Smart Modem SM2400 can be used to communicate with traffic controllers, variable message signs, dial-up to the web or most any other dial-up application that requires
communications over the public switched network.

The GDI Smart Modem SM2400 offers 3 data rates from 300 to 2400 bps. The GDI Smart Modem SM2400 is “AT” command set compatible with auto-dial, auto-answer, and auto-speed detect. The GDI Smart Modem is compatible with the GDI Smart Modem SM2400 dial-up modem. The internal fused power supply eliminates the common
“brick” external power supply. The unit is also available in a 170 Plug-in form factor.

General Specifications

Quadrature Amplitude Modulation FSK and DPSK

Serial Interface
RS232C compatible, Asynchronous 7 data bits with any parity type, 1 or stop bits, or 8 data bits with Mark or parity, 1 or 2 stop bits

Data Rates 2400, 1200, 300 bps Automatic selection for highest error free rate

Compatibility Bell 103, Bell 212A, V.22, V.22 bis,

Asynchronous full or half duplex
Automatic/manual call originate and answer

PC Compatible Serial Plug and Play

Data & Line Interfaces
Data RS232C and RS485 via DB-9S
Phone handset RJ11
Phone line RJ11

Telephone Line Interfaces
FCC compliant Part 68 and Part 15
Line Interface RJ11, 600 ohms, Public
Switched Network
Ring Equivalent 1 Bel
Return Loss Better than 14dB from 200 to 4000 Hz
Dialing Pulse and Tone
DTMF Duration and spacing 50 to 255 ms

Receiver Performance
Signal to Noise Ratio -10 dB
Dynamic Range -10 dBm to –45 dBm
SD, RD, OH, CD,AA and HS

Receiver Carrier Detect
Off-to-On Threshold -43 dBm
On-to-Off Threshold -48 dBm
Hysteresis Greater than 2 dB

Transmit and Receive Frequencies
Data Carrier 1800 +/- 0.5 Hz
Calling Tone 1300 +/- 10 Hz
Answer Tone 2100 +/- 15 Hz
Receive Frequency +/- 14 Hz
Transmit Level Fixed at –11 +/- 2 dBm


Allows storage of two user profiles and four 36 digit dial

strings. Eliminates switches and jumpers.

Power Requirements


Voltage 90 to 130 VAC (Standard)

180 to 260 VAC (optional)

Frequency 60 Hz +/- 3 Hz

Power 4 watts maximum


Voltage +12 and –12 VDC +/- 5%

Power 200 ma



Size 1.5" H x 5.5" W x 8.5" D

Weight 2 lbs


Temperature Range -37 to 74oC

Humidity 5 to 95% non-condensing


SM2400 (170 Plug-in)
SM2400SA (standalone)

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