Nokia 6680 RM-36 Service Manual page 346

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• Measurements can be done with an oscilloscope, a probe and signal generator.
• WCDMA receiver has to be active before RX IQ-signals can be measured. Procedure is explained in
section "Receiver troubleshooting".
• Apply –50 dBm RF-signal (unmodulated) from a signal generator to the module jig antenna
connector and use frequency 2140.1 MHz (Channel 10700)
• Remember to change the correct RX channel also to Phoenix "RX control" window!
• Check RX I and RX Q -signals in following test points:
RX I (positive): Connect the probe to test point J7508
-
RX I (negative): Connect the probe to test point J7509
-
RX Q (positive): Connect the probe to test point J7510
-
RX Q (negative): Connect the probe to test point J7511
-
• Signal in all four test points should be about the same. Output should be a sine wave with
frequency 100 kHz and amplitude about 650 mV.
Change the signal generator to frequency 2142.0 MHz (Channel 10700)
•
• Signal in all four test points should be about the same. Output should be a sine wave with
frequency 2.0 MHz and amplitude about 550 mV.
4.2.4.1 RF operating voltage VBAT_ASIC ok?
See section
•
4.2.4.2 RFBUS signals ok?
• GSM receiver has to be active before RFBUS signals can be measured. Procedure is explained in
section "GSM RX chain activation for manual measurements". Also WCDMA/GSM transmitter and
WCDMA receiver activation can be used for the measurement but then RFBUS -signals don't
necessarily look like in figures mentioned below.
Measurements can be performed with an oscilloscope and a probe. Check all five RF BUS signals:
•
RFBUSDAT: Connect the probe to J7504. Typical RFBUSDAT -signal is shown in section
-
"RFBUSDAT (GSM
RFBUSCLK: Connect the probe to J7505. Typical RFBUSCLK -signal is shown in figures
-
(GSM RX)"
RFBUSENA: Connect the probe to J7506. Typical RFBUSENA -signal is shown in the figure
-
and RFBUSENA (GSM
RXRESETX: Connect the probe to J7515. RXRESETX -signal is a constant 2 V DC-signal after GSM or
-
WCDMA transceiver has been activated the first time after phone boot up. The level of this signal
should be about 0 V before transceiver activation.
• TXRESETX: Connect the probe to J7517. TXRESETX -signal is a constant 2 V DC-signal after GSM or
WCDMA transceiver has been activated the first time after phone boot up. The level of this signal
A-100
"RF operating voltage VBAT_ASIC ok?"
RX)".
and "RBUSCLK and RFBUSENA (GSM
RX)".
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Appendix A: RF Troubleshooting
RX)".
6.5.9.3
"RFBUSCLK
"RFBUSCLK