Kenwood NXR-700 Service Manual

Also see for NEXEDGE NXR-700: Brochure Instruction manual Service manual Instruction manual Instruction manual

Contents

NXR-70076■ Traceability Procedure of IC17 (Flash Memory of RF control MPU)Confi rmation of Power Source VoltageTest Point Normal Output VoltageIC329 (pin 5) 3.3VDCCorrect conditionConfi rmation of Reset controlTest Point Normal Control VoltageR137 3.3VDC(either end of R137 is OK)Correct conditionParts other than IC17 are malfunctioning.■ Traceability Procedure of IC325 (The Modem control MPU)Confi rmation of Power Source VoltageTest point Normal output voltageIC15 (pin 3) 3.3VDCCorrect conditionConfi rmation of Clock frequencyTest Point Proper FrequencyR566 14.7456MHz(either end of R566 is OK)Correct conditionConfi rmation of Reset controlTest Point Normal Control VoltageIC303 (pin 1) 3.3VDCCorrect conditionParts other than IC325 are malfunctioning.Confi rmation of IC329 (pin 5) output.Remove R159 and if 3.3VDC, one of IC17, IC34,IC28, IC32, IC33, or IC40 is malfunctioning.Confi rmation of the clock and reset control of IC34Confi rmation of clock frequency:If 14.7456MHz cannot be confi rmed at the edges ofR195:X1 is malfunctioning or the circuit around X1 is mal-functioning.If the clock oscillation amplitude is weak at the edg-es of R195, the drive circuit in IC34 is malfunction-ing.Reset control confi rmationRemove R232 and then confirm the voltage of thepad on the opposite side of IC34.If 3.3VDC, IC34 is malfunctioning.If both Clock and Reset control are working prop-erly, one of IC17, IC28, IC32, IC33, or IC40 is mal-functioning.AbnormalconditionAbnormalconditionConfi rmation of IC15 (pin 3) outputRemove R484. If 3.3VDC, IC325 is malfunctioning.If the oscillation of 14.7456MHz cannot be con-fi rmed:X301 is malfunctioning or the circuit around X301 ismalfunctioning.The clock oscillation amplitude is weak:The drive circuit in IC325 is malfunctioning.Remove R559 and confirm the voltage on the padat the reverse side of IC325:If 3.3VDC, IC325 is malfunctioning.AbnormalconditionAbnormalconditionAbnormalconditionTROUBLE SHOOTING