Classification Confidential

Date

Apr 23, 2007

Version

V 1.0 ENG

Halley RF Troubleshooting

and Maintenance Guide

ASUSTeK Computer Inc.

R&D Division

IA R&D Department

1

Table of Contents

Table of Contents .................................................................................................1

1. Equipment Requirements ...............................................................................2

(1) Software requirements..................................................................................2

(2) Hardware requirements ................................................................................2

(3) Instrument requirements...............................................................................2

2. Test Environment Setup ..................................................................................3

(1) Instrument linking ........................................................................................3

(2) Fixture ..........................................................................................................4

3. RF Block Diagram ...........................................................................................6

(1) GSM block diagram .....................................................................................6

(2) WCDMA block diagram ..............................................................................7

4. RF Tx/Rx Path and Test Points.......................................................................8

(1) GSM Tx/Rx path and test points ..................................................................8

(2) WCDMA Tx/Rx path and test points ......................................................... 11

5. Procedures of Repair .....................................................................................14

(1) Repair Process A: check calibration files...................................................16

(2) Repair Process B: GSM/WCDMA wireless test ........................................18

(3) Repair Process C: GSM/WCDMA conductive test....................................20

(4) Repair Process D1: GSM Tx debug ...........................................................22

(5) Repair Process E1: GSM Rx debug ...........................................................30

(6) Repair Process D2: WCDMA Tx debug ....................................................37

(7) Repair Process E2: WCDMA Rx debug ....................................................44

2

1. Equipment Requirements

(1) Software requirements

XML

Hermon database

RFSender

IFL V1.2.1

GSM/WCDMA performance test tool

GSM/WCDMA debug tool

(2) Hardware requirements

PCB fixture

RF adapter

RF cable

USB cable

(3) Instrument requirements

PC

Wireless communication test set (Agilent 8960, R&S CMU200, Anritsu 8820)

Spectrum analyzer (Span > 3.0 GHz)

RF signal generator (up to 3.0 GHz)

High impedance RF probe with DC block

Digital multimeter

Power supply

3

2. Test Environment Setup

(1) Instrument linking

4

(2) Fixture

Fixture appearance

PCB on fixture (front view)

5

PCB on fixture (rear view)

Calibration and RF test setup

6

3. RF Block Diagram

(1) GSM block diagram

7

(2) WCDMA block diagram

8

4. RF Tx/Rx Path and Test Points

How RF signal is transmitted and received between components on Halley PCB

is explained in this section. It is important to realize RF transmission path (Tx) and

receiving path (Rx) before starting out to repair NG PCB, because engineers need to

choose proper test points which assist us to distinguish where the problem is. The

following paragraphs describe both Tx and Rx path in GSM and WCDMA bands. The

related test points are listed in the following figures.

(1) GSM Tx/Rx path and test points

GSM Tx path

Transceiver, RF6001 (U19), receives IQ signals coming from baseband, and

output signals of RF6001 Pin22 and Pin23 are transmitted into the buffer of receiver,

RF2722. Then RF2722 Pin12 and Pin13 emit the low band signal (GSM900) and high

band signals (DCS1800 or PCS1900) separately.

In the low band, output signal from RF2722 Pin12 passes through C235,

attenuator (U21) and RF3166 (U22) Pin7, power amplifier, sequentially. Transmission

and receiving switch (U20), also named T/R switch, gets the amplified signal from

RF3166 Pin23 via matching circuits. RF signal coming from T/R switch Pin15 is

transmitted to connector (Con6) and radiated via the GSM antenna of Halley.

In the high band, output signal from RF2722 Pin13 passes through C243,

attenuator (U23) and RF3166 (U22) Pin1, power amplifier, sequentially. Transmission

and receiving switch (U20), also named T/R switch, gets the amplified signal from

RF3166 Pin30 via matching circuits. RF signal coming from T/R switch Pin15 is

transmitted to connector (Con6) and radiated via the GSM antenna of Halley.

GSM Rx path

RF signals, receiving from base stations via the GSM antenna, pass through

connector (Con6) and T/R switch Pin15 (U20) sequentially. There are three output

pins of T/R switch, including Pin2, Pin4, and Pin5. The output path which RF signal

is transmitted depends on band selection of T/R switch.

In GSM900 band, the output signal which is transmitted from T/R switch Pin2

passes through SAW filter (BPF1) and matching circuits sequentially. Upon RF2722

(U18) receiving the signal, it is amplified in the Low Noise Amplifier (LNA) of the

receiver, down converted the signal’s frequency and transformed into IQ signals. The

IQ signals from RF2722 Pin20, Pin21, Pin22, and Pin23 travel to the transceiver

RF6001 (U19). The transceiver RF6001 transfers the signals to the baseband signals.

9

In DCS1800 band, the output signal which is transmitted from T/R switch Pin5

passes through SAW filter (BPF3) and matching circuits sequentially. Upon RF2722

(U18) receiving the signal, it is amplified in the Low Noise Amplifier (LNA) of the

receiver, down converted the signal’s frequency and transformed into IQ signals. The

IQ signals from RF2722 Pin20, Pin21, Pin22, and Pin23 travel to the transceiver

RF6001 (U19). The transceiver RF6001 transfers the signals to the baseband signals.

In PCS1900 band, the output signal which is transmitted from T/R switch Pin4

passes through SAW filter (BPF1) and matching circuits sequentially. Upon RF2722

(U18) receiving the signal, it is amplified in the Low Noise Amplifier (LNA) of the

receiver, down converted the signal’s frequency and transformed into IQ signals. The

IQ signals from RF2722 Pin20, Pin21, Pin22, and Pin23 travel to the transceiver

RF6001 (U19). The transceiver RF6001 transfers the signals to the baseband signals.

10

GSM Tx/Rx test points

Bottom side

Top side

11

(2) WCDMA Tx/Rx path and test points

WCDMA Tx path

The output signal from transmitter MAX2390 Pin2 travels to SAW filter (BPF4),

and RMPA2259 Pin2 sequentially. The boosted power coming from RMPA2259 Pin8

passes through isolator (U26), duplexer Pin1 (U28), and connector (Con7). At last, the

RF signal is radiated via WCDMA antenna of Halley.

WCDMA Rx path

RF signal in WCDMA, receiving from base stations via the WCDMA antenna,

passes through connector (Con7) and duplexer Pin3 sequentially. MAX2391 Pin1

(U31), built-in LNA, receives the signal from duplexer. Then the signal is transmitted

to SAW filter (BPF5) and returns to receiver MAX2391 again. After down converting

the signal’s frequency and transforming into IQ signals, the IQ signals from

MAX2391 Pin20, Pin21, Pin22, and Pin23 travel to baseband.

12

WCDMA Tx/Rx test points

Bottom side

13

Top side

14

5. Procedures of Repair

The following flow chart shows repair’s procedures that comprise a series of

repair processes. The purpose of each repair processes is to check the cause of

different RF performance defects.

Calibration files should be confirmed first to guarantee existence of RF

parameters in FDI. After wireless and conductive test, engineers can find out where

the problem is. Therefore, engineers properly recognize that the defect comes from

either antenna contact or RF circuits. If the defect results from RF circuit, the next

procedure is to disassemble and debug Tx/Rx path.

It is very important that conductive and wireless test should be done again to

make sure that Halley operates properly after any debug process. Each repair process

is described specifically in following sections.

15

16

(1) Repair Process A: check calibration files

The flow chart of Repair Process A is shown below.

The purpose of this repair process is to check calibration files in FDI. Without

calibration files, Halley can’t keep good RF performance. Moreover, making a phone

call might operate improperly.

17

The detail steps of Repair Process A are listed as follows.

a. Clean boot: push “Direction key” upward first, and then press “Power key”.

When “WARNING” is shown on panel, press “Send key”. The figure below shows

clean boot method.

b. Check calibration files in FDI by using IFL tool. There shall be three

calibration files in FDI. The names of the calibration files are as follows,

PcCalData.nvm

aplp_rf_analysis.nvm

aplp_rf_calibration.nvm.

c. If all calibration files exist in FDI, go to next Repair Process B: Wireless test.

Otherwise, the PCB which calibration files are lost needs to be calibrated.

18

(2) Repair Process B: GSM/WCDMA wireless test

The flow chart of Repair Process B is shown below.

19

The purpose of this repair process is to distinguish problems between antenna

and RF circuit that cause weak RF performance. Besides, wireless test is a previous

analysis of all RF tests. Moreover, engineers utilize wireless test to confirm that

antenna performance is not affected after re-assembling.

The detail steps of Repair Process B are listed as follows.

a. Put a golden sample of Halley into a shielding box and link to a tester (Agilent

8960 or R&S CMU200). Then, record its location and path loss.

b. At the same position that the golden sample was located, put problematic

Halley into the shielding box. After that, wait for Halley registering at the tester.

c. After attaching to the network, make a phone call.

d. Measure maximum output power and sensitivity. The test requirements of

maximum output power and sensitivity shall not exceed the range listed in the

following table.

e. If any of previous steps (b. ~ d.) is failed, consequently enter next process,

Repair Process C: GSM/WCDMA conductive test.

f. If all previous steps (b. ~ d.) are passed, it means that nothing happens.

Therefore, need to clarify customer’s complaints and try to understand user’s

behaviors.

Channel

Power

Level

Power

Requirements

Sensitivity

Requirements

GSM 900

62 5

29.3~35.3

dBm

Refer to

golden sample

DCS 1800

700 0

26.0~32.0

dBm

Refer to

golden sample

PCS 1900

661 0

26.0~32.0

dBm

Refer to

golden sample

WCDMA

10700

All up

(24 dBm)

20.8~25.5 dBm

Refer to

golden sample

20

(3) Repair Process C: GSM/WCDMA conductive test

The flow chart of Repair Process C is shown below.

21

The purpose of this repair process is to reduce the scope of RF problems. Due to

smaller measuring tolerance of conductive test, it is helpful to focus on either GSM

band or WCDMA band. Moreover, engineers can obtain further information about Tx

and Rx path of RF circuits.

The detail steps of Repair Process C are listed as follows.

a. Connect Halley which needs to repair with a tester by a RF cable. After that,

wait for registering at the tester. (Agilent 8960 or R&S CMU200)

b. After attaching to the network, make a phone call.

c. Measure maximum output power and sensitivity. The test requirements of

maximum output power and sensitivity shall not exceed the range listed in the

following table.

d. If any of previous steps (a. ~ c.) is failed, consequently execute “MMI test

program” (also named “2577”) and disassemble Halley later for RF hardware circuit

debug (Repair Process D1: GSM Tx debug or Repair Process D2: WCDMA Tx

debug).

e. If all steps (a. ~ c.) are passed but the previous process, wireless test, is failed,

it means antenna shall be replaced. In another case, Halley needs verification of

conductive test and shall pass previous steps (a. ~ c.) after other successful debug

processes. At this time, the next step is to do wireless test.

Channel

Power

Level

Power

Requirements

Sensitivity

Requirements

GSM 900

62 5

31.3~33.3

dBm

-106.0 dBm

DCS 1800

700 0

28.0~30.0

dBm

-105.0 dBm

PCS 1900

661 0

28.0~30.0

dBm

-105.0 dBm

WCDMA

10700

All up

(24 dBm)

21.5~25.0 dBm

-108.2 dBm

22

(4) Repair Process D1: GSM Tx debug

The flow chart of Repair Process D1 is shown below.

23

The purpose of this repair process is to find out where the problem is on GSM Tx

path. In other words, engineers can judge the defect component on RF path by using

“Debug tool”. Debug tool makes Halley into test mode so that PA can transmit power

continuously.

The usage of debug tool can be referred to “Debug tool user guide” provided by

Halley ATS engineers. Related parameters of debug tool are prescribed in the

following table.

Channel

PCL

Tx

Frequency

PAG_Value

DAC1V

GSM 900

62 5 902.4

MHz 555 5200

DCS 1800

700 0 1747.8

MHz 560 5200

PCS 1900

661 0 1880.0

MHz 525 5200

The detail steps of Repair Process D1 are listed as follows.

GSM 900 Tx debug

a. Spectrum analyzer connects with a high impedance probe. Execute GSM

debug tool and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Tx path, including antenna pad, L59, C228, and C235. Corresponding

locations are shown in “4. RF Tx/Rx Path and Test Points.” Furthermore,

measurement error of RF power on each test point is unavoidable due to measurement

skills and methods of using high impedance probe.

c. Antenna pad: all components on Tx path are good if power is measured from

antenna pad within 25dBm~32dBm. In this case, engineers shall go to next repair

process, Repair Process E1: GSM Rx debug.

24

d. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if power is measured within 25dBm~ 32dBm on L59, and no signal is

measured from antenna pad. The following figure is an example of L59 signal

measurement on the spectrum analyzer.

e. C228: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if power is measured within 25dBm~ 32dBm on C228, and no signal is

measured on L59. The following figure is an example of C228 signal measurement on

the spectrum analyzer.

25

f. C235: Check whether PA (U22) is good or not. PA needs to be reworked if

power is measured within -6dBm~ 0dBm on C236, and no signal is measured on

C228. Besides, if no output power is measured on C235, transceiver (U19) needs to

be reworked. The following figure is an example of C235 signal measurement on the

spectrum analyzer.

DCS 1800 Tx debug

a. Spectrum analyzer connects with a high impedance probe. Execute GSM

debug tool and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Tx path, including antenna pad, L59, C234, and C245. Corresponding

locations are shown in “4. RF Tx/Rx Path and Test Points.” Furthermore,

measurement error of RF power on each test point is unavoidable due to measurement

skills and methods of using high impedance probe.

c. Antenna pad: all components on Tx path are good if power is measured from

antenna pad within 25dBm~32dBm. In this case, engineers shall go to next repair

process, Repair Process E1: GSM Rx debug.

26

d. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if power is measured within 25dBm~ 32dBm on L59, and no signal is

measured from antenna pad. The following figure is an example of L59 signal

measurement on the spectrum analyzer.

e. C234: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if power is measured within 25dBm~ 32dBm on C228, and no signal is

measured on L59. The following figure is an example of C234 signal measurement on

the spectrum analyzer.

27

f. C245: Check whether PA (U22) is good or not. PA needs to be reworked if

power is measured within -6dBm~ 0dBm on C245, and no signal is measured on

C234. Besides, if no output power is measured on C245, transceiver (U19) needs to

be reworked. The following figure is an example of C245 signal measurement on the

spectrum analyzer.

PCS 1900 Tx debug

a. Spectrum analyzer connects with a high impedance probe. Execute GSM

debug tool and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Tx path, including antenna pad, L59, C228, and C235. Corresponding

locations are shown in “4. RF Tx/Rx Path and Test Points.” Furthermore,

measurement error of RF power on each test point is unavoidable due to measurement

skills and methods of using high impedance probe.

c. Antenna pad: all components on Tx path are good if power is measured from

antenna pad within 25dBm~32dBm. In this case, engineers shall go to next repair

process, Repair Process E1: GSM Rx debug.

28

d. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if power is measured within 25dBm~ 32dBm on L59, and no signal is

measured from antenna pad. The following figure is an example of L59 signal

measurement on the spectrum analyzer.

e. C234: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if power is measured within 25dBm~ 32dBm on C228, and no signal is

measured on L59. The following figure is an example of C234 signal measurement on

the spectrum analyzer.

29

f. C245: Check whether PA (U22) is good or not. PA needs to be reworked if

power is measured within -6dBm~ 0dBm on C245, and no signal is measured on

C234. Besides, if no output power is measured on C245, transceiver (U19) needs to

be reworked. The following figure is an example of C245 signal measurement on the

spectrum analyzer.

30

(5) Repair Process E1: GSM Rx debug

The flow chart of Repair Process E1 is shown below.

31

The purpose of this repair process is to find out where the problem is on GSM

Rx path. In other words, engineers can judge the defect component on RF path by

using “Debug tool” and RF signal generator. Debug tool makes Halley into test mode

and keeps Rx path receiving CW (continuous wave) from the generator.

The usage of debug tool can be referred to “Debug tool user guide” provided by

Halley ATS engineers. Related parameters of debug tool and recommended output

power from the generator are prescribed in the following table.

Channel

Rx

Frequency

Generator

power

GSM 900

62

947.4 MHz

-20 dBm

DCS 1800

700

1842.8 MHz

-20 dBm

PCS 1900

661

1960.0 MHz

-20 dBm

The detail steps of Repair Process E1 are listed as follows.

GSM 900 Rx debug

a. Set RF signal generator to emit CW with corresponding frequency and

transmit power into Halley GSM connector via RF cable and a RF adapter (MS-162).

Spectrum analyzer connects with a high impedance probe. Execute GSM debug tool

and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Rx path, including L59, C653, and C184. Corresponding locations are

shown in “4. RF Tx/Rx Path and Test Points.” Furthermore, measurement error of RF

power on each test point is unavoidable due to measurement skills and methods of

using high impedance probe.

c. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if no RF signal is measured on L59.

32

d. C653: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if RF signal emitted by the signal generator is measured on L59, and no

power is detected on C653. The following figure is an example of C653 signal

measurement on the spectrum analyzer.

e. C184: Check whether SAW filter (BPF1) is good or not. BPF1 needs to be

reworked if RF signal emitted by the signal generator is measured on C653, and no

power is detected on C184. The following figure is an example of C184 signal

measurement on the spectrum analyzer.

33

DCS 1800 Rx debug

a. Set RF signal generator to emit CW with corresponding frequency and

transmit power into Halley GSM connector via a RF cable and a RF adapter (MS-162).

Spectrum analyzer connects with a high impedance probe. Execute GSM debug tool

and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Rx path, including L59, C656, and C210. Corresponding locations are

shown in “4. RF Tx/Rx Path and Test Points.” Furthermore, measurement error of RF

power on each test point is unavoidable due to measurement skills and methods of

using high impedance probe.

c. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if no RF signal is measured on L59.

d. C656: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if RF signal emitted by the signal generator is measured on L59, and no

power is detected on C656. The following figure is an example of C656 signal

measurement on the spectrum analyzer.

34

e. C210: Check whether SAW filter (BPF3) is good or not. BPF3 needs to be

reworked if RF signal emitted by the signal generator is measured on C656, and no

power is detected on C210. The following figure is an example of C210 signal

measurement on the spectrum analyzer.

35

PCS 1900 Rx debug

a. Set RF signal generator to emit CW with corresponding frequency and

transmit power into Halley GSM connector via a RF cable and a RF adapter (MS-162).

Spectrum analyzer connects with a high impedance probe. Execute GSM debug tool

and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Rx path, including L59, C655, and C195. Corresponding locations are

shown in “4. RF Tx/Rx Path and Test Points.” Furthermore, measurement error of RF

power on each test point is unavoidable due to measurement skills and methods of

using high impedance probe.

c. L59: Check whether GSM RF connector (CON6) is good or not. CON6 needs

to be reworked if no RF signal is measured on L59.

d. C655: Check whether T/R switch (U20) is good or not. T/R switch needs to be

reworked if RF signal emitted by the signal generator is measured on L59, and no

power is detected on C655. The following figure is an example of C655 signal

measurement on the spectrum analyzer.

36

e. C195: Check whether SAW filter (BPF2) is good or not. BPF2 needs to be

reworked if RF signal emitted by the signal generator is measured on C655, and no

power is detected on C195. The following figure is an example of C195 signal

measurement on the spectrum analyzer.

f. The next process returns to “Repair Process C: GSM/WCDMA conductive

test” after all Rx paths are well in GSM900 band, DCS1800 band, and PCS1900 band.

In a special case, receiver (U18) needs to be reworked if no problem is found on all

Rx paths and conductive test is still failed. Furthermore, the process returns to

wireless test under the condition of passing conductive test.

37

(6) Repair Process D2: WCDMA Tx debug

The flow chart of Repair Process D2 is shown below.

38

39

40

The purpose of this repair process is to find out where the problem is on

WCDMA Tx path. In other words, engineers can judge the defect component on RF

path by using “Debug tool”. Debug tool makes Halley into test mode so that PA can

transmit power continuously.

The usage of debug tool can be referred to “Debug tool user guide” provided by

Halley ATS engineers. Related parameters of debug tool are prescribed in the

following table.

UL Channel

Tx Frequency

Vgc DAC

WCDMA

9750 1950.0

MHz 1024

The detail steps of Repair Process D2 are listed as follows.

a. Spectrum analyzer connects with a high impedance probe. Execute GSM

debug tool and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on GSM Tx path, including antenna pad, C277, duplexer (U28) Pin1, L42, C268 Pin1,

C260, C262 Pin1, and L12. Furthermore, the signals of C268 Pin1 and C262 Pin1 are

both DC signals instead. Corresponding locations are shown in “4. RF Tx/Rx Path

and Test Points.” Moreover, measurement error of RF power on each test point is

unavoidable due to measurement skills and methods of using high impedance probe.

41

c. Antenna pad: all components on WCDMA Tx path are good if power is

measured from antenna pad within -46dBm~-37dBm. In this case, engineers shall go

to next repair process, Repair Process E2: WCDMA Rx debug.

d. C277: Check whether WCDMA RF connector (CON7) is good or not. CON7

needs to be reworked if power is measured within -46dBm~-37dBm on C277, and no

signal is measured from antenna pad. The following figure is an example of C277

signal measurement on the spectrum analyzer.

42

e. U28 Pin1: Check whether duplexer (U28) is good or not. Duplexer needs to be

reworked if power is measured within -46dBm~ -37dBm on U28 Pin1, and no signal

is measured on C277. The following figure is an example of U28 Pin1 signal

measurement on the spectrum analyzer.

f. L42: Check whether isolator (U26) is good or not. CON7 needs to be reworked

if power is measured within -46dBm~-37dBm on C277, and no signal is measured on

U28 Pin1. The following figure is an example of L42 signal measurement on the

spectrum analyzer.

43

g. C268 Pin1(

DC

): Check whether power detector (U28) is good or not. The

main function of power detector is to sense RF signal by means of converting RF to

DC voltage. The voltage level on C268 Pin1 shall be 1.3V ~ 1.5V as maximum output

power, approximate 23.5 dBm, is emitted. Power detector needs to be reworked if no

voltage level is measured in the situation of maximum output power.

h. C260: Check whether PA (U24) operates normally or not. PA needs to be

reworked if DC-DC converter supplies DC voltage to PA and power is measured

within -63dBm~-55dBm on C260. The following figure is an example of C260 signal

measurement on the spectrum analyzer.

i. C262 Pin1(

DC

): Check whether DC-DC converter (U32) is good or not. The

voltage level on C262 Pin1 shall be 2.7V ~ 2.9V as RF power is emitted. DC-DC

converter needs to be reworked if no DC voltage is measured on C262 Pin1.

44

(7) Repair Process E2: WCDMA Rx debug

The flow chart of Repair Process E2 is shown below.

45

The purpose of this repair process is to find out where the problem is on

WCDMA Rx path. In other words, engineers can judge the defect component on RF

path by using “Debug tool” and RF signal generator. Debug tool makes Halley into

test mode and keeps Rx path receiving CW (continuous wave) from the generator.

The usage of debug tool can be referred to “Debug tool user guide” provided by

Halley ATS engineers. Related parameters of debug tool and recommended output

power from the generator are prescribed in the following table.

DL Channel

Rx Frequency

Generator Power

WCDMA

10700

2140.0 MHz

-30 dBm

The detail steps of Repair Process E2 are listed as follows.

a. Set RF signal generator to emit CW with corresponding frequency and

transmit power into Halley WCDMA connector via a RF cable and a RF adapter

(MS-162). Spectrum analyzer connects with a high impedance probe. Execute

WCDMA debug tool and set parameters in the above table.

b. Use the high impedance probe to sequentially measure RF power of test points

on WCDMA Rx path, including C277, C293, L27 and L14. Corresponding locations

are shown in “4. RF Tx/Rx Path and Test Points.” Furthermore, measurement error of

RF power on each test point is unavoidable due to measurement skills and methods of

using high impedance probe.

46

c. C277: Check whether WCDMA RF connector (CON7) is good or not. CON7

needs to be reworked if no RF signal is measured on C277. The following figure is an

example of C277 signal measurement on the spectrum analyzer.

d. C293: Check whether duplexer (U28) is good or not. Duplexer needs to be

reworked if no power is measured on C293. The following figure is an example of

C293 signal measurement on the spectrum analyzer.

47

e. L27: Check whether receiver (U31) is good or not. Receiver needs to be

reworked if no power is measured on L27. The following figure is an example of L27

signal measurement on the spectrum analyzer.

f. L14: Check whether BPF5 is good or not. BPF5 needs to be reworked if no

power is measured on L14. The following figure is an example of L14 signal

measurement on the spectrum analyzer.

48

g. The next process returns to “Repair Process C: GSM/WCDMA conductive

test” after there is no problem in WCDMA Rx path. Moreover, the process returns to

wireless test under the condition of passing conductive test.