CCS Technical Documentation
RH-34 Series Transceivers
Troubleshooting - GPS
Issue 1 11/2003 Confidential ©2003 Nokia Corporation
RH-34
Troubleshooting - GPS CCS Technical Documentation
Contents
Page No
Troubleshooting - Global Positioning System (GPS) Engine........................................ 3
GPS General Block Diagram .......................................................................................3
GPS RF Schematic ......................................................................................................3
GPS Testing .................................................................................................................4
GPS RF Probing Setup ................................................................................................7
GPS RF Probing Measurements................................................................................ 8
Page 2 ©2003 Nokia Corporation Confidential Issue 1 11/2003
RH-34
CCS Technical Documentation Troubleshooting - GPS
Troubleshooting - Global Positioning System (GPS) Engine
The RH-34 handset supports 800 Amps and 800 CDMA / 1900 CDMA + GPS with IS 2000
capability. The RH-34 engine supports CDMA and GPS functionality for Enhanced 911
(E911) services.
GPS circuitry utilizes RF signals from satellites stationed in geosynchronous orbit to
determine latitude and longitude of the handset. The GPS circuitry and the cellular
engine (CE) circuitry are completely separate in the handset. The GPS circuitry is located
almost exclusively on the secondary side of the PWB, underneath the display module.
GPS General Block Diagram
FilterFilter
LNA
Xtal
16.368MHz
GPS RF Schematic
Synthesiser
IF = 4.092MHz
GPS RF
AGC
Amp
4
ADC
TRF5101
Cellular Baseband
GPS RF Chip (N001)
Rx Data
Out
GPS
Baseband
Ref Clk
Filter 1 (Z001)
Filter 2 (Z002)
F Input
Circuits located on Bottom Layer
Issue 1 11/2003 Confidential ©2003 Nokia Corporation Page 3
Circuits located on Top Layer
RH-34
Troubleshooting - GPS CCS Technical Documentation
GPS Testing
1 Set Local Mode.
2 Inject -110dBm tone @ 1575.52MHz at GPS connector (X001) with signal gener-
ator or call box.
Signal Generator
Signal Generator
RF OUT
RF OUT
3 Open “GPS Control” from the “BB/Hwd” drop-down menu.
4. Execute the GPS Quick Test.
5. Analyze Results: See next figures.
Page 4 ©2003 Nokia Corporation Confidential Issue 1 11/2003
RH-34
CCS Technical Documentation Troubleshooting - GPS
5a. Self-Test Failure:
• Repeat Steps 1-5 for first failure. If the test still fails, continue.
• Inspect all GPS circuit elements around D051.
• If pass visual inspection, then replace D051.
5b. Oscillator Failure:
• Inspect all GPS circuit elements around D051.
• If pass visual inspection, then replace B002.
D051
B002
Top Layer
5c. CW Test Failure:
• Check that signal generator is on and sourcing a signal to the GPS RF input port (X001).
• Inspect all GPS RF circuit elements.
• Inspect all GPS circuit elements around D051.
• If all visual inspection looks good, then replace GPS RF IC (N001).
Issue 1 11/2003 Confidential ©2003 Nokia Corporation Page 5
RH-34
Troubleshooting - GPS CCS Technical Documentation
INSPECT!
Page 6 ©2003 Nokia Corporation Confidential Issue 1 11/2003
RH-34
CCS Technical Documentation Troubleshooting - GPS
GPS RF Probing Setup
1 Turn on the GPS Receiver
2 Inject -25dBm tone @ 1575.52MHz at GPS Connector (X001) with signal gener-
ator or Call Box.
Signal Generator
Signal Generator
RF OUT
RF OUT
3 Continue to the GPS RF Probing Diagram diagram which follows, and measure
probe points with either a FET probe and a spectrum analyzer set at center frequency 1575.25MHz, Span = 500kHz, or a voltmeter as specified.
Issue 1 11/2003 Confidential ©2003 Nokia Corporation Page 7
RH-34
Troubleshooting - GPS CCS Technical Documentation
GPS RF Probing Measurements
2
1
4
PT Description Value Instrument
LNA output 1575.25MHz @ -19.5dBm spectrum analyzer
3
1
2nd BPF output 1575.25MHz @ -21dBm spectrum analyzer
2
TXCO supply V
RF_GPS
2.78V (DC) voltmeter
3
TXCO output freq 16.368MHz @ +6dBm spectrum analyzer
4
Page 8 ©2003 Nokia Corporation Confidential Issue 1 11/2003
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