User Guide

CCS Technical Documentation RF Troubleshooting Instructions
RH-12/RH-28
Issue 1 02/04 Nokia Corporation Page 5
Introduction
This document is the troubleshooting guide for RH-12/RH-28. On the following pages
you will find a step-by-step fault finding procedure and reference measurements at the
relevant signal points.
Notes on reference measurements
• LF & DC signals are measured with Textronix 100 MHz Scope
(TDS3014) and P3010 13pF probe.
• RF signals are measured with R&S FSIQ 7GHz Spectrum Analyzer and
Agilent resistive divider probe (10dB, 500ohm).
• Please be aware that the RF connector on service adaptor is leaking
power (into air) and acts as noise source when probing on RX chain. In
1800 band the problem is most severe while there is no external LNA to
amplify the signal above the noise level like in the 1900 band. In 900/
850 band the leakage is not as high due to lower frequency.
• GSM SA settings: RBW=500kHz, VBW=500kHz.
• Bluetooth SA settings: RBW=2MHz, VBW=2MHz.
• All reference measurements were made on a RH-12 phone (GSM900).
RH-28 (GSM850) results should be very similar.
• RF loss Module Repair Jig: 0.3dB (low bands), 0.4dB (high bands).
• RF loss RF Adaptor: 0.4dB (low band), 0.7dB (high bands).