2.Electrical Description

All electrical connections to the TT4031 (SE-GM29) are designed to meet the standard air (4 kV) and contact (8 kV) discharge ESD tests, of EN 301 489-1.

The modem uses the following industry standard connectors:

RJ11 6-way (power connector)

RJ9 4-way (handset connector)

SIM card reader

FME male coaxial jack (antenna connector)

Sub-D socket, 9 pin (RS232 serial port)

2.1Power Connector

An RJ11 6-way connector, as shown and described below, serves as a means of supplying and controlling d.c. power to the modem.

The supply voltage, VCC, required by the modem is in the range 5 V - 32 V d.c. Application of the supply voltage does not switch the modem on. To do so an additional active-high control signal, TO_IN, must be applied for > 0.2 s .

A second active-high control signal, HR_IN, can be used to switch the modem off when applied for 1 - 2 seconds, or can be used to perform a hardware reset when applied for > 3.5 s.

TO_IN and HR_IN are referenced to GND (pin 6 on the connector). VCC and GND are reverse polarity and overvoltage protected

Owner’s Manual

Rev 1.0

Page 29 of 29