Tx Uhf Lo (N7000) Troubleshooting - Nokia 3155 Rf Description And Troubleshooting

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Tx UHF LO (N7000) Troubleshooting

There are two fixed LOs, 3296.16~3395.88MHz for cell band and 3700~3819.90MHz for
PCS band. This is the only LO for up-conversion. Be sure to monitor the control voltage at
R7001. When the N7000 LO is locked, this control voltage should be between 1.2 and
1.8Vdc.
1
4
Table 17 shows the description for each component in
Test
Description
Point
1 Lock voltage
2 N7000: Measure voltage by probing
the top of the chip.
3 VIO
4 Vcc_Vco
5 VR6
6 F_REF_TX to N7000
ISSUE 1 07/2005
2 6 3 5
Figure 49: Tx UHF LO layout and test points
Table 17: Tx UHF Test Point Values
©2005 Nokia Corporation
3155/3155i (RM-41), 3152 (RM-61)
RF Description and Troubleshooting
PCS PA
Figure 49.
Value
DC between 1.2 and 1.8V
Cell channel 384: 3346.08MHz, -55 to -65dBm
PCS channel 600: 3760MHz, -54 to -65dBm
1.8V
2.3V
2.8V
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Cell PA
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