Rf Troubleshooting - Nokia NPD-1 Series Troubleshooting - Rf

CCS Technical Documentation

RF Troubleshooting

If TX power is low, turn on transmitter in local mode using Phoenix. Check:
• current (0.7 – 1 A for max power, mode and channel dependent.)
• perform visual inspection of PWB under microscope to check proper
placement, rotation, and soldering of components
• Look for presence of TX signal on spectrum analyzer at the correct fre-
quency. If signal is not on frequency, check in 100 MHz span. If signal is
present but off frequency, check synthesizer. If signal is not present, or
present but low in amplitude, use probing Tables 1 through 5 to deter-
mine where in the chain the fault occurs, with AGC PDMs set for known
transmit power as listed in Table 1
• Check that AGC PDMs are set for desired TX power according to
Tables 1 and 3, and ensure that AGC voltages are correct
• according to Tables 2 (cell/AMPS) and 4 (PCS), check the LOs for
proper frequency and amplitude
• ensure power supplies to transmitter have correct voltage, as per
Table 12
If Receiver is not working properly, turn on transmitter in local mode and check:
• turn on receiver with Phoenix, inject a signal into the receiver
• check the RSSI level and AGC PDM according to Table 6
• perform a visual inspection of the PWB under a microscope to check
proper placement, rotation, and soldering of components
• use probing Tables 6 through 11 to measure signal levels at various
points in the chain and determine where in the chain the fault lies
• according to tables 3a through 4b, check the LOs for proper frequency
and amplitude
• ensure power supplies to receiver have correct voltage as per Table 5
If phone won't make a call:
• ensure phone is in normal mode (i.e., ensure the phone is searching for
a signal, i.e., net server is on).
• ensure Preferred Roaming List (PRL) is loaded into phone
Issue 1 11/2002
Nokia Corporation
Troubleshooting — RF
Confidential
NPD-1
Page 5