Helgo Troubleshooting Diagram - Nokia NHM-1 Series Troubleshooting Instructions

CCS Technical Documentation

Helgo Troubleshooting diagram

troubleshooting
Check with oscilloscope:
-
TXI/TXQ signals
-
VR1A, VR2, VR3, VR4, VR5, VR7 = 2.8V
-
VREFRf01 = 1.35V
-
Helgo serial interface
-
TXP/TXC signals
Yes
Check with RF probe
VCO out signal level
3589.6 MHz (GSM900)
3495.6 MHz (GSM1800)
Yes
Check modulator
output components,
No
Replace faulty
component(s)
Issue 1 11/03
Helgo
OK?
-10dBm,
OK?
OK?
Figure 5: HELGO troubleshooting
Nokia Corporation.
Troubleshooting instructions
No
Baseband
troubleshooting
*(When 1kOhm passive probe is used
correct measurement result by +26dB
No
Synthesizer
troubleshooting
Yes
Replace Helgo
NHM-1
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