Hytera MD78X Service Manual page 113

UHF1 (400-470MHz 25W) Information Service Manual
Description of Normal Situations:
[1] Detect the oscillation frequency of RX TP123 and TX TP111 using a spectrum analyzer.
[2] Check whether switches (Q108, Q112, Q101 and Q105) are turned on and output 3.6V
[3] Check whether the emitter voltage of the four transistors (Q106, Q110, Q100 and Q103) is about
1.8V under normal RX/TX status.
[4] Check the CV of TP124. The normal value should range from 0.5 to 4.5V.
[5] Check whether U100 is supplied by 5V and 3.3V normally.
[6] Check whether the power from TP109 to PLL is about -15dBm.
[7] Check whether TP100 outputs 19.2MHz signal.
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