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Nokia Customer Care
Troubleshooting Instructions
Company confidential
NPL-4/5/
Issue 2 05/05
Copyright
© 2005
Nokia Corporation. All rights reserved.
Page 13
The RF front-end is a triple-band direct conversion transceiver. Using direct conversion,
no intermediate frequencies are used for up- or down-conversion.
Figure 7: RF Power Supply Configuration
GSM: 869-894 MHz
925-960 MHz
DCS: 1805-1880 MHz
PCS: 1930-1990 MHz
f
f
f/4
f/4
f
f
Helgo
f/2
f/2
PLL
3296-
3980
MHz
I-signal
Q-signal
RX
I-signal
Q-signal
TX
PCS: 1850-1910 MHz
DCS: 1710-1785 MHz
GSM: 824-849 MHz
880-915 MHz
Buffer
VCTCXO
26 MHz
26 MHz
VCTCXO
AFC