MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | MAINTENANCE GUIDE
Chapter 5: Codan Radio System Testing Page 27
Figure 5-9: Receiver Balanced (and Auxiliary) Audio Output Measurement
To adjust the auxiliary balanced audio output, plug the AC-3E Control Card or CI-BC-4E Base Control
Card into the subrack using an extender card and connect the Auxiliary Balanced audio output to the
DVM input directly on the IFR 2975 (no external load is required as the internal 600 ohm load of the IFR
2975 is used). Auxiliary 1 audio output is available on pins B11 and A11, and Auxiliary 2 audio output
is available on pins C1 and C3 for the AC-3E Control Card and pins C2 and C4 for the CI-BC-4E Base
Control Card. Ensure that NO external devices (eg. tone remote adapter or IP router) are connected
to the auxiliary audio output. Adjust the Auxiliary Balanced Audio Output level adjustment (R13 for Aux
Out 1, R56 for Aux Out 2) for 0.0 dBm audio level (0.775 Vrms @ 600 ohms).
Enter the Balanced Audio Output Level and Auxiliary Audio Output Level (if used) readings on the MT-
4E Test Sheet.
There are no specifi c measurements to check Receive CTCSS, just verify that the receiver CTCSS is
operating.
Summary of Contents for MT-4E
Page 1: ...www codancomms com MT 4E Analog and P25 Digital Radio Systems MAINTENANCE GUIDE...
Page 2: ......
Page 75: ......