LG G3100, Руководство по обслуживанию

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This section shows the typical RF power levels expected throughout the receiver path. A block diagram
shows the locations of the RF measurement points and levels as shown in Fig. 3-11.
Receiver Testing Set-up
To check the receiver the test equipment should be set as the following conditions:
On a signal generator or a GSM/DCS test box, output amplitude of CW sugnal = -60 dBm at either:
947.4 MHz (CH62) when testing the GSM RX path or 1842.6 MHz (CH699) when testing the DCS
RX path. Set the DC power supply to 4.0 V.
Note: All RF values shown are only intended as a guide figure and may differ from readings taken
with other test equipment and leads. Lead and connector losses should always be taken into
account when performing such RF measurements.
Testing Receiver
Measure the RF power levels of the points which is shown in Fig. 3-9. If there are any major
difference between your measurement results and the values shown in the figure, then further
investigation about the particular point will be required. It will also be necessary to ensure that all the
following power supplies and signals which control this part of the receiver circuit are present :
1. The Control Signal of FEM (see Fig. 3-15, 16, 17)
2. RF2V8 (see Fig. 3-12)
3. 2V7_VTCXO (see Fig. 3-13)
4. 13MHz (see Fig. 3-14)
5. PLL_CLK, PLL_DATA, PLL_LE (see Fig. 3-18)
8. RX IP, IN, QP, QN (see Fig. 3-21)
This section shows the typical RF power levels expected throughout the transmitter path. A block
diagram shows the locations of the RF measurement points and levels as shown in Fig. 3-8.
Transmitter Testing Set-up
To check the transmitter the test equipment should be set as the following conditions:
1. Set the DC Power supply to 4.0 V.
2. Power up the GSM/DCS test set and then establishing a call with an attached mobile on active
mode.
3. Select Channel, TX Level and Input Level according to which parameter is required.
Note: All RF values shown are only intended as a guide figure and may differ from readings taken
with other test equipment and leads. Lead and connector losses should be always taken into
account during the measurement.
3.5 Testing Set-up and Checking Signals
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3. TECHNICAL BRIEF
A. Received RF Power Level and Checks
B. Transmitted RF Power Level and Checks