Nokia N81 Service Manual

Table of Contents
General RF troubleshooting ..................................................................................................................................4–5
Introduction to RF troubleshooting ................................................................................................................4–5
General information on RF troubleshooting ..................................................................................................4–5
RF key components ...........................................................................................................................................4–7
Non-replaceable RF components.....................................................................................................................4–8
General voltage checking .................................................................................................................................4–9
Phoenix self tests ........................................................................................................................................... 4–10
Receiver troubleshooting ................................................................................................................................... 4–11
Introduction to receiver (RX) troubleshooting............................................................................................ 4–11
VCTCXO troubleshooting ................................................................................................................................ 4–12
RX GSM850 troubleshooting.......................................................................................................................... 4–13
RX GSM900 troubleshooting.......................................................................................................................... 4–14
RX GSM1800 troubleshooting........................................................................................................................ 4–15
RX GSM1900 troubleshooting........................................................................................................................ 4–16
GSM RX chain activation for manual measurements/GSM RSSI measurement ........................................ 4–17
WCDMA receiver troubleshooting................................................................................................................. 4–18
WCDMA RX chain activation for manual measurement.............................................................................. 4–19
WCDMA RSSI measurement ........................................................................................................................... 4–20
Transmitter troubleshooting ............................................................................................................................. 4–20
General instructions for transmitter (TX) troubleshooting........................................................................ 4–20
GSM transmitter troubleshooting................................................................................................................. 4–21
TX 850/900 troubleshooting......................................................................................................................... 4–23
TX 1800/1900 troubleshooting..................................................................................................................... 4–24
Checking antenna functionality.................................................................................................................... 4–25
WCDMA transmitter troubleshooting ........................................................................................................... 4–26
WCDMA transmitter troubleshooting flowchart.......................................................................................... 4–29
RF tunings ............................................................................................................................................................ 4–29
Introduction to RF tunings............................................................................................................................ 4–29
Autotuning for BB5 ........................................................................................................................................ 4–30
System mode independent manual tunings .................................................................................................... 4–31
RF channel filter calibration.......................................................................................................................... 4–31
PA (power amplifier) detection .................................................................................................................... 4–31
GSM receiver tunings........................................................................................................................................... 4–32
Rx calibration (GSM) ....................................................................................................................................... 4–32
Rx band filter response compensation (GSM).............................................................................................. 4–35
GSM transmitter tunings..................................................................................................................................... 4–38
Tx IQ tuning (GSM).......................................................................................................................................... 4–38
Tx power level tuning (GSM) ......................................................................................................................... 4–40
WCDMA receiver tunings..................................................................................................................................... 4–42
RX calibration (WCDMA) ................................................................................................................................. 4–42
WCDMA transmitter tunings............................................................................................................................... 4–45
Tx AGC & power detector (WCDMA)............................................................................................................... 4–45
Tx band response calibration (WCDMA) ....................................................................................................... 4–51
Tx LO leakage (WCDMA) ................................................................................................................................. 4–53
List of Tables
Table 5 Rf channel filter calibration tuning limits ........................................................................................... 4–31
Table 6 RF tuning limits in Rx calibration......................................................................................................... 4–34
RM-179; RM-223
RF troubleshooting
Issue 1 COMPANY CONFIDENTIAL Page 4 –3
Copyright © 2007 Nokia. All rights reserved.

Nokia N81 Specifications

General

Display diagonal	2.4 \
Display resolution	240 x 320 pixels
Display number of colors	16.78 million colors
Ringer type	Polyphonic
Internal memory	8196 MB
Front camera type	Single camera
Rear camera resolution	1600 x 1200 pixels
Personal info management (PIM)	Alarm clock, Calculator, Calendar, Notes, To-do list
Headphone connectivity	3.5 mm
USB 2.0 ports quantity	1
Text prediction system type	T9
Multimedia Messaging Service (MMS)	Multimedia Messaging Service (MMS) is a standard way to send messages that include multimedia content to and from a mobile phone over a cellular network
Form factor	Slider
Product color	Brown
Gaming time	6 h
Browsing time	5 h
Talk time (2G)	4 h
Talk time (3G)	3 h
Battery capacity	1050 mAh
Standby time (2G)	1020 h
Continuous audio playback time	11.5 h
Continuous video playback time	4.5 h
2G standards	GPRS
Data network	wcdma
Bluetooth version	2.0+EDR
Bluetooth profiles	A2DP, BIP, DUN, FTP, GAP, GOEP, HFP, HSP, OPP, SPP
SIM card capability	Single SIM

Weight and Dimensions

Depth	102 mm
Width	50 mm
Height	17.9 mm
Weight	140 g