User's Manual

MASTR III Repeater Calibration Procedure 5/16/2011
Raytheon JPS Communications, Inc. 2-7
8/22/2011
2.1.3.6 Listen for a 1200Hz sine wave in the monitor speaker set for demodulated
audio. A P25 Handset may also be used for this step if tuned to the proper
frequency in conventional P25 mode.
2.1.3.7 Check the Symbol Deviation to verify that it is 1750Hz +/- 75Hz; adjust the
TxVcoGain to increase or decrease the deviation if necessary. Also, you
may adjust the Frequency Error by trimming the TxVcoOffset if needed.
The Constellation and Eye Diagrams are shown for reference. The
Modulation Fidelity should be better than 5% (typically<2%; SeeFigure
2-6) .
Figure 2-6 Transmitter Performance Screen
This completes Transmitter calibration. Unkey the transmitter and install a dummy load on the
Tx output in preparation for Receiver calibration
2.2 Rx Calibration
Receive calibration adjusts the P25net CC audio input level to match the radio line audio output
level and calibrates the P25net CC for the RSSI signal from the receiver.
• Rx Gain provides adjustment for the receiver line audio output entering the Channel
Card.