LG GT500 - Page 154

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4. TROUBLE SHOOTING
4.20.6 Checking RX I,Q
To verify the RX path you have to check the pk-pk level and the shape of the RX I,Q.
Feed a CW signal at 2142MHz
with a power level of –60dBm.
Figure 4-36-1. RX I,Q signal (CW:2142MHz)
Figure 4-35. RF3300, WCDMA Transceiver (Bottom)
About 2 MHz
Figure 4-36-2. RX I, Q signal
WRX_Q_P (PIN 2)
WRX_Q_N (PIN 1)
WRX_I_N (PIN 3)
WRX_I_P (PIN 4)
WRX_I_P
(PIN 4)
WRX_I_N
(PIN 3)
WRX_Q_P(
PIN 2)
WRX_Q_N(
PIN 1)