[. . . ] Version 7. 0 Line Sensor for the TransTel ML500 System The Version 7. 0 Line Sensor offers the following features when a Telco line is connected to the RJ11 Jack marked TELCO on the rear panel of the transceiver module: · · · · · · Automatic switching to cellular transmission if the telco line has been cut or tip-ring voltage is no longer present. [. . . ] However, prior to removal of the transceiver module, turn off the power supply and disconnect antenna and telephone cabling at the rear of the of the chassis. In addition, two captive black retaining screws (one in the extraction handle and one at the top of the module front panel) must be loosened. Exercise great care when extracting a transceiver module and avoid any damage to the components of the module. Two switches (SW1 and SW2 on the left upper edge of the Line Sensor board) control settings for closure of the dry contacts on the rear panel of the chassis. Switch settings from 0 through 9 result in the following actions: SWITCH SETTINGS SW2 (left switch) Duration in Increments of 0 or 2n-1 Hours 0 N=1 through 8: 1, 2, 4, 8, 16, 32, 64, or 128 hrs. n=9: indefinite number of hours or until ALARM RESET is pressed; (factory default). SW1 (right switch) Activation after 0 or 2n Minute Intervals Any setting 0 (factory default) n=0 through 8 (1, 2, 4, 8, 16, 32, 64, 128, or 255 minutes) ACTION IF TELCO LINE VOLTAGE IS LOST ACTION IF TELCO DIAL TONE IS LOST No alarm contact closure Red ALARM LED on immediately for duration set with SW2. Alarm contact closure delayed by SW1 setting; alarm contacts on for number of hours set by SW2. No alarm contact closure Red ALARM LED on immediately for duration set with SW2. [. . . ] The contacts open automatically (red ALARM LED off) when signal is again acquired or the fault condition has been corrected. 2. All rights reserved. [. . . ]