BAOJIE BJ-9900, Руководство по обслуживанию

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QUANZHOUBAOJIE ELECTRONICS CO.,LTD. Model:BJ-9900
Version:BJ-9900-0812-V1 Page 10 of 75
then launch "PTT" command to the main CPU IC1104.
When the "PTT" command is received, the main CPU IC1104 pin 45 to the "high"
position, then activates the UHF transmitter switch Q1096.
When the Q1096's UHF transmitter switch is activated, it controls the antenna switching
diode D1118, D1119, D1120, modulation switching diode Q1114, Q1115, diode switch
D1099, D1101, D1106, D1107, and APC automatic power switch Q1130, Q1131. These
activated the 430 MHz transmitter circuit.
144 MHz Signal
When you press the PTT switch, the sub CPU U2001's pin 23 to the "low" position,
then will launch the "PTT" command to the main CPU IC1104.
When the "PTT" command is received, the main CPUIC1104 pin 46 to the "high"
position, then activates a VHF transmitter switch Q1096.
When Q1096 for VHF transmitter switch is activated, it controls the antenna switching
diode D1118, D1119, D1120, modulation switching diode Q1114, Q1115, diode switch
D1099, D1101, D1106, D1107, and APC automatic power switch Q1130, Q1131. These
activated the 144 MHz transmitter circuit.
PLL Electric circuit
Main band
Come to UHF-VCO / B Q1116 part of the output buffer amplifier Q1117 and through
diode switch D1086, sent to the PLL IC1109 programmable divider. Here it is according
to the main CPU IC1104 related to the frequency division data is divided and sent to the