Receiver; General Instructions For Rx Troubleshooting - Nokia NPM-2NX Troubleshooting Manual

CCS Technical Documentation
PWRDET
PLL
RF
RX
T:
TX
U/C
UHF
V:
VCO
VHF
AF:

Receiver

General instructions for RX troubleshooting

Receiver troubleshooting is divided into three sections:
- General checking
- Local oscillator checking
- RX Chain checking
Faultfinding charts are represented for each band and more detailed troubleshooting
instructions are included. Please note that before changing ASICs or filters, all solderings
and missing components must be checked visually. After any possible component
changes phone must be re-tuned using Phoenix autotune procedure. Signal levels are not
shown in the flowcharts below because of the figures apply with specific measurement
probes. It is useful to compare the results against the reference phones.
Equipment needed for receiver troubleshooting:
- Signal generator up to 2 GHz
- Oscilloscope with 10x passive probe
- Spectrum analyzer and active probe without attenuation block or passive probe (Please
note that the signal levels mentioned in the RX troubleshooting have been measured
with an active probe.)
- PC with Phoenix SW AM version
Optional equipment:
- SINAD meter or audio analyzer for AMPS measurement
- Radio communication test set
Issue 1 07/02
Power detector module
Phase Locked Loop
Radio Frequency
Receiver
Time between pulses
Transmitter
Up converter (mixer and driver in same package)
Ultra High Frequency
Voltage of signal (measured with oscilloscope)
Voltage controlled oscillator
Very High Frequency
Audio Frequency
ãNokia Corporation
NPM-2NX
Troubleshooting
Page 27