Nokia 3520 Service Manual 7 rh21 trouble

Nokia Customer Care

RH-21 Series Transceivers

Troubleshooting

Issue 2 07/2004  2004 Nokia Corporation. Page 1

Company Confidential

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Page 2  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Contents

Page No

Troubleshooting ............................................................................................................. 5

Baseband Troubleshooting ..........................................................................................5

General testing information....................................................................................... 5

Troubleshooting ........................................................................................................ 6

Phone does not start up normally or does not stay on............................................... 8

Flash Programming does not work.......................................................................... 10

Charging .................................................................................................................. 12

Audio failures.......................................................................................................... 13

Accessory detection................................................................................................. 15

Sleep Clock ............................................................................................................. 16

User Interface .......................................................................................................... 18

Receiver Troubleshooting ..........................................................................................20

General Instructions for RX troubleshooting .......................................................... 20

Path of the received signal ...................................................................................... 20

Fault-finding charts for receiver chain .................................................................... 21

Transmitter fault-finding ...........................................................................................29

General instructions for TX troubleshooting .......................................................... 29

Path of the transmitted signal .................................................................................. 29

Fault-finding charts for transmitter ......................................................................... 29

Power control loop .................................................................................................. 32

Synthesizer fault-finding ...........................................................................................35

19.44 MHz reference oscillator............................................................................... 35

RX VHF VCO......................................................................................................... 37

TX VHF VCO ......................................................................................................... 38

UHF Synthesizer ..................................................................................................... 38

Issue 2 07/2004  2004 Nokia Corporation. Page 3

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Page 4  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Troubleshooting

The first thing to do when a problem is encountered is to carry out a thorough visual
check of the module. Make sure that:

• there are no mechanical damages

• the solder joints are OK

Note: Before changing anything, ALL SUPPLY VOLTAGES AND THE SYSTEM CLOCK / SLEEP
CLOCK should be checked.

Baseband Troubleshooting

General testing information

There are three different modes for testing and/or repairing the phone. The mode can be
selected with suitable resistors connected to BSI- and BTEMP- lines as illustrated in the
following table:

Table 1: Phone operating mode

Mode BSI- resistor

Nor-

68k 75k

BTEMP
resistor

Remarks

mal

Local 560_(<1k_) Whatever

Test > 1k 560_(<1k_) Recommended for baseband testing. Same as

local mode, but making a phone call is possi­ble.

If the corresponding resistors are connected, the MCU software automatically enters into
the local or test mode when the supply voltage is connected to the phone.

The power can be switched on by:

1 Pressing the power key.

2 Connecting the local/test mode resistors to the BSI/BTEMP lines and connecting

the battery voltage to the phone.

3 Connecting a charger.

4 Using the phone’s internal functions (real-time clock alarm).

In the local and test mode, the baseband can be controlled through MBUS or FBUS (FBUS
is recommended) connections using Phoenix service software.

Issue 2 07/2004  2004 Nokia Corporation. Page 5

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Troubleshooting

Note: Most of the baseband repair actions require removing the baseband shield. The shield must not
be removed unless separately authorized by the program.

Note: The phone’s ESN has to re-written to the UEM, if the UEM is replaced. This can be done only in
Central Service.

The baseband troubleshooting instructions include the following topics:

1Power up

2 Flash programming

3Audio

•Earpiece

•Microphone

4 Charging

5 Accessory detection

6 Sleep clock

7 User interface

•Display

•Lights

•MIDI

•Vibra

• Keyboard

Power-up faults

Power-up sequence

1 The UEM acts as a HW master during start up

• Vbatt limits: 2.1V for internal state machine, 3V triggering whole startup

• Regulator sequencing

• HW "core" regulators "on": Vio, Vcore, VR3, Vflash1

• These regulators supply the processors, memory chip interfaces and clock source
in RF

• Reset releasing delay

Page 6  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

• Supply voltages stabilize to their UEM HW default values

• RFCLK grows to full swing

• The core is ready to run but waiting for the PURX release

• Reset releasing

• The UPP releases the SLEEPX up to the "non sleep" state to prevent the UEM
switching the regulators "OFF"

2 MCU starts running the Bootstrap Code

• written in stone/ UPP internal ROM

• the program checks if there is any reason for the FDL mode (Flash Down Load)

• If there is an executable code in FLASH and there is no reason for FDL, the MCU
starts running the MCU program from FLASH

3 MCU runs the FLASH MCU code

• the phone initialization, user interfaces, internal blocks, etc.

• Core regulator voltage setting for required DSP speed

• Initializes the DSP and concerning HW

• Releases DSP reset -> DSP starts running

Note: In the following figure, the RF_Clk frequency appears to be lower than 19.44MHz because of a
too low oscilloscope sampling frequency (2kS/s).

Figure 1: Power-up sequence

Issue 2 07/2004  2004 Nokia Corporation. Page 7

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

1 Power key pressed

• After 20ms, UEM enters RESET MODE if VBAT>Vmstr+

• VFLASH1, Vana, Vcore, Vio, and VR3 goes high

• VCTCXO enabled by VR3 -> RFClk 19.44 MHz running

2Purx released

• Purx released by UEM, UEMINT goes high for 100 ms, SleepX goes high, and
SleepClk (32 KHz) starts running.

3 Software running

• Default value for Vcore is 1.5 volts and, if software is running, Vcore will rise to

1.8 volts

• Cbus (1.08MHz) and Dbus clocks start running

Phone does not start up normally or does not stay on

Note: In the case of power-up faults, it is not possible to force the phone on by disabling the watchdog.
Instead, measurements should be taken immediately when the power key is pressed or when the bat­tery voltage is connected to the phone (local / test mode).

The easiest way to check if the software is running when the phone takes an abnormal
amount of current is to measure the cbusclk and Vcore.

The Dbus clock (programmable 9.72MHz) is not automatically visible in the test and local
modes.

Page 8  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Figure 2: Fault tree, phone does not power up

Issue 2 07/2004  2004 Nokia Corporation. Page 9

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Flash Programming does not work

Flash programming procedure

1 The phone communicates with the prommer via the production test pattern,

using the following signals:

• FBUSTX (serial data to phone)

• FBUSRX (serial data from phone)

• MBUS (serial clock for FBUSRX)

• VPP (External flashing voltage for speed up flashing)

• The BSI line is also used when initializing flashing (battery connec- tor)

2 When the phone is powered (VBAT>3V), the MBUS and FBUSTX lines are pulled

up internally by the phone.

3 The prommer sends a command to the UEM, using FBUSRX, to enter the Flash-

mode. During the sending of this command, the prommer keeps the BSI line high
and MBUS is used as a serial clock.

4 When the Flash-mode command is acknowledged, UEM enters the Flash-mode

and releases reset (PURX) to MCU.

5 After reset is released, UPP checks if there is a request for the Bootstrap code

(that resides in the UPP ROM).

6 The request for Bootstrap is the MBUS pulled down by the prommer (if the boot-

strap is not requested, the bootstrap code jumps to FLASH SW).

7 If the Bootstrap code is requested, UPP enters the Flash-mode and sets FbusTX to

'0' as an acknowledgement to the prommer. This is an indication that UPP can
run, at least, the fixed Bootstrap code – although it is not able to run the FLASH
code. UPP then sends an UPP-ID to the prommer via the FBUSTX line.

8 After the prommer has received the UPP-ID, it sends a corresponding Secondary

Boot Code to the phone via FBUSRX. The Secondary Boot Code, when run in UPP,
requests UPP to send information to the prommer about the flash type and other
HW-related parameters about the device to be flashed.

9 The prommer then sends the Algorithm Code corresponding to the HW parame-

ters, and this algorithm, when run in UPP, takes over handling the MCUSW trans­fer to Flash.

10 12 volts can be supplied to Vpp (by the prommer) to speed up flashing.

11 The FLASH Program includes a package of MCU and DSP software and all default

parameters for the phone. The tuning values will be added/rewritten during the

Page 10  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Flash/Alignment phase.

Flash programming error codes

The various error codes can be seen from the "FPS-8 Flash" in Phoenix.

The underlined text in the following table means that the item under consideration is
being used for the first time in the flashing sequence.

Error Description Not working properly

C101 "The Phone does not set FbusTx line high after

the startup."

Vflash1
VBatt
BSI and FbusRX from prommer to
UEM.
FbusTx from UPP->UEM->Prom­mer(SA0)

C102 "The Phone does not set FbusTx line low after

the line has been high. The Prommer generates
this error also when the Phone is not connected
to the Prommer."

PURX(also to Safari)
VR3
Rfclock(VCTCXO->Safari->UPP)
Mbus from Prommer->UEM­>UPP(MbusRx)(SA0)
FbusTx from UPP->UEM->Prom­mer(SA1)
BSI and FbusRX from prommer to
UEM.

C103 "Boot serial line fail." Mbus from Prommer->UEM-

>UPP(MbusRx)(SA1)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

C104 "MCU ID message sending failed in the Phone." FbusTx from UPP->UEM->Prom-

mer

C105 "The Phone has not received Secondary boot

codes length bytes correctly."

Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

C106 "The Phone has not received Secondary code

bytes correctly."

Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

Issue 2 07/2004  2004 Nokia Corporation. Page 11

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

C107 "The Phone MCU can not start Secondary code

correctly."

C586 "The erasing status response from the Phone

informs about fail."

C686 "The programming status response from the

Phone informs about fail."

Cx81 "The Prommer has detected a checksum error in

the message, which it has received from the
Phone."

Cx82 "The Prommer has detected a wrong ID byte in

the message, which it has received from the
Phone."

A204

"The flash manufacturer and device IDs in the
existing Algorithm files do not match with the
IDs received from the target phone."

Cx83

"The Prommer has not received Phone
acknowledge to the message."

Cx84

"The Phone has generated NAK signal during
data block transfer."

Cx85

"Data block handling timeout"

UPP

Flash

Flash

FbusTx from UPP->UEM->Prom­mer

FbusTx from UPP->UEM->Prom­mer

Flash
UPP
VIO/VANA?
Signals between UPP-Flash
Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

Cx87 "Wrong MCU ID." RFClock

UPP(Vcore)

Star­tup for

Required startup for flashing Vflash1

VBatt
flash­ing

Charging

Note: The charging voltage and current can be checked by connecting the phone to the service soft­ware and reading the ad- converter values of the vchar and ichar.

If charging fails when the ACP-9 or the LCH-9 is used, but works with ACP-7, ACP-8, and
LCH-8, check that the charge control pin of the system connector is connected to the
ground.

Page 12  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Figure 3: Fault tree, charging

Audio failures

In case of audio failures, there are three possibilities to check the audio lines.

1 Make a phone call against tester and check audios.

2 If the earpiece/XMIC fails: Feed a 1Khz signal to the XMIC line and measure the

signal from the earpiece line. The Audio test box JBA-8 is needed. The Audio loop
(Audio test/Ext In Hp Out) must be switched on by the Phoenix service software.
This loop will connect audios only through the UEM. In this case, the UPP is not
used.

If the internal microphone/XEAR fails: Feed the tone to the microphone and measure the
signal from the XEAR line. The Audio test box JBA-8 is needed. The Audio loop (Audio
test/Hp In Ext Out) must be switched on by the Phoenix service software. This loop will
connect audios only through the UEM. In this case, the UPP is not used.

Issue 2 07/2004  2004 Nokia Corporation. Page 13

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

3 Run the audio-loop self-test with Phoenix (BB Self Tests/

ST_EAR_DATA_LOOP_TEST). This loop will test the ear-data/mic-data lines

between the UPP and the UEM.

Earpiece or external microphone line does not work

Figure 4: Fault tree, earpiece failure

Page 14  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Microphone or XEAR line does not work

Figure 5: Fault tree, microphone failure

Accessory detection

1 Start the phone in the normal mode when checking for accessory detection.

2 The Ad-converter value of the hookint-line can be checked with the Xmic switch

on an MJ-8 test jig. Changes normally from high to low when no accessory is
connected.

3 When the headset HDC-5 is connected, the hookint-value should be between

600 and 800.

Issue 2 07/2004  2004 Nokia Corporation. Page 15

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Figure 6: Fault tree, accessory detection

Sleep Clock

Missing/nonfunctional sleep clock causes

• Entering sleep mode fails (higher current consumption -> shorter standby time)

• Baseband self-tests cannot be run

• Phone clock (on display) does not function properly

Page 16  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Figure 7: Fault tree, sleep clock

Issue 2 07/2004  2004 Nokia Corporation. Page 17

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

User Interface

Display/Keyboard lights do not work

Figure 8: Fault tree, Display/Keyboard lights

Page 18  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Display does not work

Figure 9: Fault tree, Display does not work

Issue 2 07/2004  2004 Nokia Corporation. Page 19

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

MIDI does not work

Check speaker B180 and the following components: N180, R100, R181, R182, R183,
R184, C183, C180, C184, C181, C182, C179, L180, and L181

• No sound: Try using a known good SALT speaker instead. If there is still no sound,
change the UEM (D200)

• Weak sound: Use the Audio test in Phoenix to set the SALT speaker parameters
(frequency, strength). If it does not affect the sound level, change the SALT
speaker.

Vibra does not work

Check spring connectors and C307 and C308.

• No vibration: Try using a known good vibra instead. If there is still no vibration,
change the UEM (D200)

• Weak vibration: Use the Vibra test in Phoenix to set the vibra’s parameters (fre­quency, duty cycle). If it does not affect the magnitude of the vibration, change
the vibra.

Keyboard does not work

Check that there is no dirt between the dome sheet and the PWB. If the keyboard still
does not operate normally, try to use the Keyboard test in Phoenix to see if the pressed
key is identified. If it is not identified, change the UPP (D400).

Receiver Troubleshooting

General Instructions for RX troubleshooting

Start the Phoenix software and use it to start the required RX mode of the mobile phone.
The troubleshooting flowchart is divided into three steps: (1) general checking, (2) local
checking, and (3) RX-chain checking. Always use an RF cable connected from an external
RF connector to the analyzer via (RF power) attenuator. This is important to protect the
analyzer against excessive RF power and to prevent leakage of undesired RF power into
the cellular frequencies.

1 Start the Phoenix software and select the TX mode under Testing (AMPS, DAMPS,

or TDMA1900).

2 It is useful to select the mid channel (383 for AMPS/DAMPS or 1000 for

TDMA1900) and the power level 2.

Note: Before changing ASICs or filters, all solderings and missing components must be checked visu­ally. After any possible component changes, the phone must be tuned with the Phoenix autotune SW.

Path of the received signal

Block level description of the receiver:

Page 20  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

(Antenna/ext RF) – Diplexer – Duplexer – Low Noise Amplifier (LNA) – RX band filter –
First mixer – 135.54 MHz RX IF filter – IF-amplifier – second mixer – 14 kHz low-pass fil­ter – adjustable IQ amplifier – Baseband.

Fault-finding charts for receiver chain

AMPS

Figure 10: Fault tree, AMPS

Issue 2 07/2004  2004 Nokia Corporation. Page 21

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Page 22  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

d

Nokia Customer Care Troubleshooting

Check RF level at RX

IF filter input at 135.54

MHz

Y

Check RF level at RX

IF filter output at

135.54 MHz

Y

N

Check RF level at J 751

and J752 at 2034.06

MHz

Y

Change SAFARI

(N801)

N

Change RX IF f i lter

(Z830)

N

Start synthesizer

troubleshoot

Note !
Check all discr et e c omp onents an

voltages ar ound S AFARI

Check RX I and Q

signals at I: J801(+),

J803(-) and Q:

J804(+), J802(-)

Y

Check UEM and start

baseband troubles hoot

N

Check RF level by

L730 without having

electrical co nt ac t at

271.08 MHz

Change SAFARI

(N801)

N

Start synthesizer

troubleshoot

Y

Issue 2 07/2004  2004 Nokia Corporation. Page 23

RH-21 Company Confidential

Note!

g

Troubleshooting Nokia Customer Care

TDMA800

Since the same physical signal path is used for both analog and digital modes at the
lower band, there is no need for additional troubleshooting in the digital mode. So if the
digital mode at the lower band is not working properly, start the analog mode trouble­shooting.

TDMA1900 (only dualband)

Only EXT RF connector –> 1st IF needs separate troubleshoot at upper band. After down
conversion (RF –> 135.54 MHz), both lower and upper band use the same signal path.

Figure 11: Fault tree, TDMA1900 troubleshooting

Apply 1960.02 MH z =

ch 1000 -110 dBm

signal to external

RF-connector X900.

Y

These tests are done
in local mode by usin
RF Test UI.

Enable loop back BE R

using RF Test UI and

check sensitivity: -110

dBm BER < 3%

N

N

Check UHF Vc (from

C773) V: 2. 2 . ..2.6 V

Y

Check RXVHF Vc

(from C720). V: 0.7

...1.3

Y

Y

N

N

TDMA1900

RX-chain is OK

Start synthesizer

troubleshooting

Start synthesizer

troubleshooting

Page 24  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Issue 2 07/2004  2004 Nokia Corporation. Page 25

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Table 2: Flash programming error codes

Error Description Not working properly

C101 "The Phone does not set FbusTx line high after

the startup."

Vflash1
VBatt
BSI and FbusRX from prommer to
UEM.
FbusTx from UPP->UEM->Prom­mer(SA0)

C102 "The Phone does not set FbusTx line low after

the line has been high. The Prommer generates
this error also when the Phone is not connected
to the Prommer."

PURX(also to Safari)
VR3
Rfclock(VCTCXO->Safari->UPP)
Mbus from Prommer->UEM­>UPP(MbusRx)(SA0)
FbusTx from UPP->UEM->Prom­mer(SA1)
BSI and FbusRX from prommer to
UEM.

Page 26  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

C103 "Boot serial line fail." Mbus from Prommer->UEM-

>UPP(MbusRx)(SA1)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

C104 "MCU ID message sending failed in the Phone." FbusTx from UPP->UEM->Prom-

mer

C105 "The Phone has not received Secondary boot

codes length bytes correctly."

C106 "The Phone has not received Secondary code

bytes correctly."

C107 "The Phone MCU can not start Secondary code

correctly."

C586 "The erasing status response from the Phone

informs about fail."

C686 "The programming status response from the

Phone informs about fail."

Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

UPP

Flash

Flash

Cx81 "The Prommer has detected a checksum error in

the message, which it has received from the
Phone."

Cx82 "The Prommer has detected a wrong ID byte in

the message, which it has received from the
Phone."

A204

Cx83

Cx84

Cx85

Issue 2 07/2004  2004 Nokia Corporation. Page 27

"The flash manufacturer and device IDs in the
existing Algorithm files do not match with the
IDs received from the target phone."

"The Prommer has not received Phone
acknowledge to the message."

"The Phone has generated NAK signal during
data block transfer."

"Data block handling timeout"

FbusTx from UPP->UEM->Prom­mer

FbusTx from UPP->UEM->Prom­mer

Flash
UPP
VIO/VANA?
Signals between UPP-Flash
Mbus from Prommer->UEM­>UPP(MbusRx)
FbusRx from Prommer->UEM­>UPP
FbusTx from UPP->UEM->Prom­mer

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Cx87 "Wrong MCU ID." RFClock

UPP(Vcore)

Star­tup for
flash­ing

Required startup for flashing Vflash1

VBatt

Page 28  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Transmitter fault-finding

General instructions for TX troubleshooting

Always use RF cable connected from external RF connector to analyzer via (rf-power)
attenuator. This is important to protect analyzer against excessive rf-power and not to
let leak unwanted rf-power to the cellular frequencies.

Start Phoenix software and select TX mode under testing (AMPS, DAMPS, or TDMA1900).
Select mid channel (383 for AMPS/DAMPS or 1000 for TDMA1900) and power level 2.
Select random data for digital mode of operation.

After any component change, tune the phone with Phoenix autotune SW.

Path of the transmitted signal

AMPS/DAMPS

UEM TX I/Q DA-converters -> I/Q modulator and Digital gain step amplifier (SafariSafari)

-> IF-BPF -> Upconverter+driver -> BPF -> PA -> Coupler (Power detector) -> Duplex­filter -> Diplexer -> EXT RF-connector -> Antenna

TDMA1900 (ONLY DUALBANDER)

UEM TX I/Q DA-converters -> I/Q modulator and Digital gain step amplifier (Safari) ->
IF-BPF -> Upconverter + driver (Safari) ->Balun -> BPF -> PA->Coupler (Power detector)

-> Duplex-filter -> Diplexer -> EXT RF-connector -> Antenna

Power detection and power control circuit belongs under power control part of this
guide.

Fault-finding charts for transmitter

AMPS

Start Phoenix software and set phone to the Analog mode. Set channel 383 and Power
level 2. Connect RF cable to EXT RF connector and connect cable to Spectrum analyze
input, and measure RF level. Notice insertion loss of the cable and attenuations.

Issue 2 07/2004  2004 Nokia Corporation. Page 29

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Page 30  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

TDMA800

The transmitter chain is exactly the same as AMPS mode, with the exception of the IPA
current. Therefore it is important that AMPS has no faults.

Issue 2 07/2004  2004 Nokia Corporation. Page 31

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

TDMA1900 (only dualbander)

TDMA1900 mode and DAMPS mode have a common RF modulator, making it important
that the DAMPS mode has no faults.

Power control loop

Basically power detection is done with the Power detector module and power control is
done inside Safari. Power detection is basically similar for both bands, except both bands
have individual couplers.

Page 32  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

Note !

See PWRDET vs. Output
power curve

Is PWRDET vs.

output power OK?

See chart below.

N

Check VR2 and

RFTEMP .

Check C930, C931

and PWRDET

module.

Y

N

Is DAC value vs.

PWRDET (mV) OK?

Detected voltages are described in the next table and diagram.

TYPICAL DETECTED VOLTAGES AT POWER LEVELS PL2…PL10 FOR DUALBANDER

800A 800D 1900D

Pout TXPWRDET Pout TXPWRDET Pout TXPWRDET

PL dBm dac mV dBm dac mV dBm dac mV

2 26.5 633 1671 27.3 696 1839 27.3 662 1746
3 22.5 393 1038 23.3 433 1142 23.3 405 1069
4 18.5 237 625 19.3 261 688 19.3 245 648
5 14.5 141 372 15.3 155 410 15.3 147 387
6 10.5 82 215 11.3 90 237 11.3 84 222
7 6.5 46 120 7.3 50 132 7.3 46 122
8 - - - 3.3 27 70 3.3 24 64
9 - - - -0.7 13 33 -0.7 11 30

10 - - - -4.7 5 12 -4.7 5 12

NOTE: DAC VALUES MAY VARY ABOUT +/- 20%
NOTE: TXPWRDET is difference between TX on burst and off burst.

Check UEM
(BaseBand)

Issue 2 07/2004  2004 Nokia Corporation. Page 33

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

2000

1800

1600

1400

Detected voltage [mV]

1200

1000

800

600

400

200

0

246810

Power level

800A

800D

1900D

TYPICAL DETECTED VOLTAGES AT POWER LEVELS PL2…PL10 FOR SINGLE BANDER

800A 800D

Pout TXPWRDET Pout TXPWRDET

PL dBm dac mV dBm dac mV

2 25.5 559 1475 27.3 671 1771
3 21.5 388 1023 23.3 465 1228
4 17.5 234 618 19.3 281 742
5 13.5 140 371 15.3 168 445
6 9.5 81 215 11.3 98 258
7 5.5 45 120 7. 3 54 144
8 - - - 3.3 31 82
9 - - - -0.7 15 40

10 - - - -4.7 5 14

NOTE: DAC VALUES MAY VARY ABOUT +/- 20%
NOTE: TXPWRDET is difference between TX on burst and off burst.

Page 34  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

2000

1800

1600

1400

1200

1000

800

600

Detected voltage [mV]

400

200

0

2345678910

Power level

800A

800D

Synthesizer fault-finding

There are four oscillators generating the needed frequencies for the RF section:

19.44 MHz reference oscillator, 2GHz UHF VCO, TX VHF cascade amplifier VCO, and
RX VHF VCO integrated in Safari. RX VHF frequency is fixed at 271.08 MHz and TX VHF
has two fixed frequencies: 361.08 MHz for lowband and 363.6 MHz for upper band. The
VCO operating frequencíes are controlled by the Safari PLL circuit. All locals are locked to
stable 19.44MHz reference oscillator.

The frequency range for 2GHz UHF VCO is 2009.1 … 2125.53 MHz. The output frequency
range for the lower band is from 2009.1 to 2059.02 MHz. In upper band, the output fre­quency range from the UHF VCO is from 2031.81 MHz to 2125.53 MHz.

A practical way to check out the synthesizer status is to measure control voltage of the
VCO from the Integrator capacitor. If voltage is stable and reasonable, local oscillators
are running correctly.

19.44 MHz reference oscillator

The 19.44 MHz oscillator frequency (G790) is controlled by UEM. This 19.44 MHz signal
is connected to Safari, PLL-circuits, and from Safari to UPP.

All synthesizers use divided VCTCXO signal as a reference signal for Phase-locked loop to
provide correct LO-frequency.

Baseband also needs a reference signal where it can generate the necessary clock signals
and VCTCXO output signal is also buffered and connected to UPP.

Issue 2 07/2004  2004 Nokia Corporation. Page 35

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Fault-finding chart for 19.44 MHz oscillator

2

Change

VCTCXO

OK

2.No

START HERE!

Is VCTCXO

oscillating?

19.44MHz

C792

2.78 V

No

R792

OK

1

OK

1.No

Check voltage

Check resistor

OK!

Page 36  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

RX VHF VCO

The RX VHF VCO signal is used to generate receiver Intermediate frequency. RX VHF VCO
has one fixed frequency (271.08 MHz). Operating frequency is locked in Phase-locked
loop.

RX VHF VCO output signal is fed to Safari. The inside of the Safari signal is divided into
the Phase detector and RX parts. Before I/Q modulator frequency is divided by 2.

Fault-finding chart for RX VHF VCO

Measure oscillator frequency over L730 coil. Don´t connect probe to pads!

AMPS, CH383

Issue 2 07/2004  2004 Nokia Corporation. Page 37

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

TX VHF VCO

The TX VHF VCO signal is used to generate transmitter Intermediate frequency. TX VHF
VCO has two fixed frequencies (361.08 MHz for lower band and 363.6 MHz for upper
band). Operating frequency is locked in Phase-locked loop and frequency is divided by
two before modulator.

Fault-finding chart for TX VHF VCO

AMPS, CH383 -> TX VHF frequency 361.08 MHz

TDMA1900, CH1000 -> TX VHF frequency 363.6 MHz

4

Check components:

C740, C741, C742, R741,

R742, R743 and

C749, C750, L750

3

Check resonator

components:

V744, C745, L746,

C747, C748

4.No

OK

3.No

Change

cascade amplifier

OK

Is oscillator locked

5.No

1

START HERE

to 361.08 MHz

or 363.6 MHz

2.No OK

Check operating

voltage:

4.75 V

at R745

5

N750

2

OK

6.No

Yes

No

OK

OK

6

Change
SAFARI

OK!

Check:

L751, R745

UHF Synthesizer

The UHF Synthesizer consists of an external 2GHz UHF VCO, loop filter and an integrated
PLL in the Safari RF IC. Safari T IC contains stages like counters, prescaler, divider by two,
phase and frequency comparator, and a charge pump circuit which allows two opera­tional modes—analog and digital. The UHF VCO Oscillation frequency is from 2009.1MHz
to 2125.53 MHz.

In the upper band (TDMA1900), 2 GHz synthesizer frequency is fed straight to mixers. In
the lower band (AMPS and TDMA800), 2 GHZ UHF VCO frequency signal is first divided
by two inside Safari and then that divided signal is fed to mixers. The output frequency

Page 38  2004 Nokia Corporation. Issue 2 07/2004

Company Confidential RH-21

Nokia Customer Care Troubleshooting

of the VCO depends on the DC control voltage, which is controlled by the PLL circuit
inside Safari.

Fault-finding chart for UHF Synthesizer

Issue 2 07/2004  2004 Nokia Corporation. Page 39

RH-21 Company Confidential
Troubleshooting Nokia Customer Care

Page 40  2004 Nokia Corporation. Issue 2 07/2004