E-Gsm900 - Nokia NHL-2NA Series Troubleshooting Instructions

NHL-2NA
Power control circuitry consists of discrete power detector ( common to E-GSM900 and
GSM1800 bands ) and error amplifier internal to HAGAR. There is a directional coupler
connected between PA output and antenna switch. It is a dual-band type and has input
and outputs for both systems. Dir. coupler takes a sample from the forward going power
with certain ratio. This signal is rectified using a Schottky-diode and produces a DC-sig-
nal after filtering.

E-GSM900

Page 12
Figure 2: E-GSM900 TX Troubleshooting Setup steps
1 Place the phone in the test jig
File → Choose Product → Calypso
2
3 From 'Toolbar' set operating mode to Local
Maintenance → Testing → RF Controls
4
5 Select band 'GSM900'
6 Set Active unit to 'Tx'
7 Set Operation mode to 'Burst'
8 Set TX data type to 'Random'
9 Set Rx/Tx channel to 37
10 Set Tx PA mode to 'Free'
11 Set power level to 5
¤Nokia Corporation
CCS Technical Documentation
Issue 1 07/02