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CCS Technical Documentation
Troubleshooting - RF
RH-48
Issue 1 11/2003
© 2003 Nokia Corporation         Confidential
Page 19
Tx System Block Diagram
Figure 10 illustrates a simplified block diagram of the transmitter. The figure shows every 
major component from I and Q baseband to the antenna port.
Note: See the Schematics chapter for an RH-48 transmitter schematic.
Figure 10: Tx system block diagram
Receiver Troubleshooting
Rx IF
Use Phoenix to perform the following steps for troubleshooting the receiver. Together 
with the VCO frequency and level verification, this test should be the first test for a non-
working receiver. This test verifies the entire receiver chain, from input connector to 
baseband output.
1 Inject a CW signal 881.82MHz or 881.22MHz (CH-384 offset by 300KHz) at a 
fixed –75dBm power level. If you do not have a signal generator, use the CALL 
BOX in AMPS mode on Channel 374 or 394 (10 channels away from 
channel 384).