Hytera PD502, Руководство по обслуживанию, Страница: 99 / 136

UHF1(400-470MHz) Troubleshooting Flow Chart
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[2] Output voltage by U302 PIN5 or input voltage by Q6004 PIN4 is about 3.3 V.
[3] Vgs: about 0.1 V; Vsd: about 3.3 V (in the case of no signal reception).
[4] For Q6006, Vbe: about 0.76 V; Vce: about 0.95 V; for Q6007, Vbe: about 0.7 V; Vce: 0.85 V (in the
case of no signal reception).
[5] Cut off the front-end circuit, and input a 58.05 MHz IF signal at C6009 to test IF sensitivity. Normally,
the IF sensitivity is -109 dBm.
[6] Frequency of Q6003: 55.8 MHz.
[7] Frequency of L6013: 18 MHz.
[8] Input a -30 dBm RF signal in the antenna port and test at RP1. Normally, gain>10 dB, output
signal>-20 dBm.
[9] Input a -30 dBm RF signal in the antenna port and test at C6092 (do not cut off the back-end circuit).
Normally, gain>1 dB, output signal>-29 dBm.
[10] C6093 output signal frequency: RF-IF, signal amplitude>2 dBm.
[11] For input of a -80 dBm signal from L6028, gain>25 dB, output signal>-55 dBm; for input of a -30
dBm signal, output signal>-20 dBm.
[12] The input signal in the antenna port, with standard tuning information (AF=1 KHz
，
FM=3 KHz), is -47
dBm.
6.3
Transmitter Circuit
Caution
The following checks must be operated with a power supply of 7.4 V.