User Guide

Technical Documentation
NHB–3
PAMS
Troubleshooting
Original 26/97
Page 3
NHB–3 TROUBLESHOOTING INSTRUCTIONS
Contents
Introduction 6
General 6
Baseband Troubleshooting 7
PWR Button Fault 8
Display Selftest Failed 9
No Registration to the System (no serv) 10
Audio Fault 11
Flash Programming ; part 2 13
Flash Programming ; part 3 14
Flash Programming ; part 4 15
Some BB measurements for reference 16
Power circuitry 17
Repairing Instructions for Flash Faulty Units 18
RF Tuning Fails 19
Calib Temperature Sensor 19
AFC Fails 19
RSSI Fails 19
TXI/TXQ Tuning 20
Power Measuring 20
Power Tuning 20
Calib BATT_VOLTAGE = 6.0 V 20
Calib CHARGE_VOLTAGE = 6.0 V 20
Repairing instructions for RF unit 21
Common features 21
Duplex filter 21
NHB–3 Receiver Functional Description 22
Front–end amplifier V501 22
RX–Filter Z505 22
First Mixer V511 22
First Local Buffer V512 22
IF–amplifier V521 22
IF–filter 23
Second Mixer V531 23
Second Local Buffer V532 23
If–amplifier V541 23
IF–filter Z541 23
AGC–amplifier 23