LG GDK-20W User Manual

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GDK-20W DIGITAL WIRELESS KEY TELEPHONE SYSTEM     
 
 
26
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 3.4.3 RGU connector and protection switch setting 
 
Following table shows the connector and switch on GDK-20W MBU. 
Switch 
ISSUE 1 
Manufacturer 
setting 
Description Remark 
Pin 1&2 short: 50Hz ring signal(sine wave) 
CN23 
 
RGU plugged: 25Hz ring signal(square wave)
Dependent on country 
adaptation. 
ON: For database protection. 
1-1 ( OFF) 
OFF: For system default. 
Turn ON the switch 
after system power on.
SW 1 
1-2 (OFF) 
OFF : Loop back OFF 
OFF (Always) 
 
The MBU has a two position DIP switch(SW1). The following is the function of each switch position :   
 
 
 
Knob 1      System data base initialization when power on 
 
 
          -. On : Do not initialize system data base when power on. 
              -. Off : Initialize system data base when power on. 
 
 
Knob 2      ISDN Loop Back on 
 
 
          -. On : Loop Back on 
                           -. Off : Loop Back off  
 
Before programming the system, SW1(knob 1) should be placed in the Off position and turn the system power off and on 
to initialize the system database to default. Once the database has been initialized, SW(knob 1) should be placed in the 
on position to protect the database in the memory. Refer to Figure 3.4.3.