Transmitter Troubleshooting; Low Tx Power; Cell Transmitter Setup - Nokia RH-77 Troubleshooting Manual

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Transmitter Troubleshooting

Low Tx Power

Use Phoenix to turn on the transmitter in Local Mode, and check the following:
• Verify the current (0.7 - 1A for max power, mode, and channel dependent).
• Use a microscope to visually inspect the PWB for proper placement, rotation, and
soldering of components.
• Look for the presence of a Tx signal on the spectrum analyzer at the correct
frequency:
• If the signal is not on frequency, check in the 100 MHz span.
• If the signal is present but off frequency, check the synthesizer. Most likely,
one of the synthesizers is not locked, or the VCO has no output signal.
• If the signal is not present, or is present but low in amplitude, use the
probing tables to determine where in the chain the fault occurs.
• Verify that the AGC PDMs are set for the desired Tx power as listed in the Tx AGC
Tuning table on page 11, and ensure that the AGC voltages are correct.
• Check the synthesizers for proper frequency and amplitude.
• Ensure that the power supplies to the transmitter have the correct voltage.

Cell Transmitter Setup

Use the following steps to set up the mobile terminal for Tx troubleshooting in Phoenix.
1. Open the Phone Control dialog box.
Issue 01 04/2005
Figure 3: Phone Control dialog box for Tx troubleshooting
©2005 Nokia Corporation
RF Description and Troubleshooting
Company Confidential
2118 (RH-77)
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