Fault-Finding Chart For Rx Vhf Vco; Tx Vhf - Nokia RH-41 Series Troubleshooting Instructions

CCS Technical Documentation

Fault-finding chart for RX VHF VCO

3. Replace Taco

TX VHF

The TX VHF signal is used to generate transmitter Intermediate frequency. TX VHF VCO
has one fixed frequency (361.08). Operating frequency is locked in Phase locked loop. TX
VHF VCO output signal is divided by 2 and fed to the modulator.
3. Replace Taco
Issue 2 09/2003
1. START HERE
Is frequency locked to
OK
271.08MHz?
2. No
1. No
2. Check resonator
1
components:
L730, C740, C741,
R741
Figure 17: Fault tree:
1. START HERE
Is frequency locked to
OK
361.08MHz?
2. No
1. No
2. Check resonator
components:
L746, C720, C721,
R721
Figure 18: Fault tree: TX VHF
Nokia Corporation
Troubleshooting Instructions
Yes
OK
RX VHF
Yes
OK
Confidential
RH-41
OK
OK
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