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Appendix H: Viavi CX300 Tests
MAINTENANCE GUIDE | MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS
Deviation Level:
The deviation level adjustment is not required when connecting the transmitter in a repeater configuration
using LVDS Serial Data. The audio level / deviation level adjustment can be done on both the Tx Balanced
Audio Input and the Auxiliary Balanced Input (1 and 2). The Auxiliary Balanced Input is only available on the
AC-3E Control Card or CI-BC-4E Base Control Card�
Change the Audio Filter (near the top left corner) from 0.3-3.4 KHz BP to 15KHz LP as shown in Figure H-21 for a
more accurate deviation reading without CTCSS encode. If the transmitter has CTCSS encode, leave the Audio
Filter on 0.3-3.4 KHz BP. The RF Power and Distortion meter can also be changed to the Oscilloscope, if desired.
To adjust the transmitter balanced input, ensure that the AC-3E or CI-BC-4E Control Card is NOT plugged into
the subrack. AF Generator A1 is configured to inject a 1.0 KHz tone at -8.0 dBm (0.308 Vrms) into the transmitter
balanced input.
Figure H-21: Transmitter Deviation Measurement