External Automatic Filters  R&S XU 4200 
 3.81 6166.5368.02.01 
3.7.2.2  Cabling 
Instructions 
1.  Connect the X-cross adapter R&S®KG42-Z75  to the RS-485 interface 
of the radio. In case of the transceiver R&S XU 4200 the filter must be 
always connected to the TX module via X7. 
2.  Connect the filter to the X-cross adapter R&S®KG42-Z75. 
 
 
 
 
 
 
 
Fig. 3.78  R&S External automatic filter connection. 
3.7.2.3  Configuration 
Setting using  
the R&S ZS 4200 
Use the Service and Maintenance Tool R&S ZS 4200 to activate the 
R&S external automatic filter. 
1.  Set the “Motor Tuned Telsa Filter” parameter to “Enable” on the radio. 
 
Note: The X-cross adapter converts the radios' serial protocol into a 
parallel BCD signal required for the R&S filter. 
Note: The operation of the Service and Maintenance Tool R&S ZS 4200 is 
described in detail in the corresponding operating manual. 
3.7.2.4  Limitations/Notes 
Limitations 
Please note that there are certain limitations to radio operation if the 
R&S external automatic filter is used: 
  Enabling the R&S external automatic filter will reduce the frequency 
range of the radio to 118 MHz … 155.9916 MHz (although the R&S 
filter supports a wider frequency range) 
 
Note: If more than one radio is used, each radio needs its separate filter. 
Note: The timeout for tuning the filter is set to 60 seconds. If the filter has 
not tuned to the correct setting by this time, the radio will generate a CBIT 
warning. 
 
 
 
 
 
 
Radio 
S4200 
 
X-Cross 
Adapter 
 
KG42-Z75 
 
Filter 
 
R&S Fx22x 
MU
X1
X7