CCS Technical Documentation RH-27 Series Transceivers Troubleshooting - GPS Issue 1 11/2003 Confidential ©2003 Nokia Corporation
RH-27 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 .........................................................................................
RH-27 Troubleshooting - GPS CCS Technical Documentation Troubleshooting - Global Positioning System (GPS) Engine The RH-27 handset supports 800 Amps and 800 CDMA / 1900 CDMA + GPS with IS 2000 capability. The RH-27 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.
RH-27 Troubleshooting - GPS CCS Technical Documentation GPS Testing 1 Set Local Mode. 2 Inject -110dBm tone @ 1575.52MHz at GPS connector (X001) with signal generator or call box. Signal Generator 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.
RH-27 Troubleshooting - GPS CCS Technical Documentation 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).
RH-27 Troubleshooting - GPS CCS Technical Documentation INSPECT! Page 6 ©2003 Nokia Corporation Confidential Issue 1 11/2003
RH-27 Troubleshooting - GPS CCS Technical Documentation GPS RF Probing Setup 1 Turn on the GPS Receiver 2 Inject -25dBm tone @ 1575.52MHz at GPS Connector (X001) with signal generator or Call Box. Signal Generator 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.
RH-27 Troubleshooting - GPS CCS Technical Documentation GPS RF Probing Measurements 2 1 3 4 PT Description Value Instrument LNA output 1575.25MHz @ -19.5dBm spectrum analyzer 2nd BPF output 1575.25MHz @ -21dBm spectrum analyzer TXCO supply VRF_GPS 2.78V (DC) voltmeter TXCO output freq 16.