GDI SM336 SM336SA 33.6 Dialup Modem

GDI SM336 33.6 Dialup Modem
SM336 (170 Plug-in) SM336SA (standalone)
GDI Smart Modem SM336
1-301-924-7400 ext. 17

* Standard “AT” Command Set
* Dual RS232/RS485 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
* Standalone or 170 Plug-in Card


The GDI Smart Modem SM336 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 SM336 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 SM336 offers 26 data rates from 300 to 33,600 bps. The GDI Smart Modem SM336 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 SM336 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

Modulation Quadrature Amplitude Modulation FSK and DPSK

Serial Interface 115.2 kbps max, V.24/V.28, V.34  RS232/RS485 compatible

Data Rates 33.6, 31.2, 28.8, 26.4, 24, 21.6, 19.2, 16.8, 14.4, 12, 9.6, 7.2, 4.8, 2.4, .3 Kbps

Automatic selection for highest free rate

Compatibility As a Data Modem

Bell 103, Bell 212A, V.22A/B, V.22bis, V.32, V.32bis, and V.34

As a Fax Modem

V.17, v.21 channel 2, v.27ter, v. and V.33

Data Compression V.42bis, MNP5

Error Correction V.42 LAPM, MNP2-4, MNP10

Loop Tests V.54 Loop 2 (RDL) and Loop 3

Modes 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



Receiver Performance

Signal to Noise Ratio -26 dB

Dynamic Range -12 dBm to –42 dBm

Ring Detect Sensitivity 38 VRMS

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


DTR On/Off

RS485 Data Standard or Inverted

RS485 Control Lines Standard or Inverted

Power Requirements


Voltage 90 to 130 VAC (Standard)

180 to 260 VAC (optional)

Frequency 60 Hz +/1 3 Hz

Power 6 watts maximum


Voltage +12 & -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


SM336 (170 Plug-in)

SM336SA (standalone)

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