Nokia NEM-4 Series Troubleshooting Instructions page 85

CCS Technical Documentation
Antenna Switch (TX/RX switch)
The antenna Switch works as a diplexer for the RX and TX signals. Moreover, it sup-
presses the TX harmonics generated by the PA. The antenna switch is controlled by the
Mjoelner RF ASIC using the control signals CONT1, CONT2 and CONT3. The following
table shows the possible different states.
CONT1 CONT2
[Volt] [Volt]
0 0
0 0
0 0
0 2.7
2.7 0
Issue 1 09/2003
Company Confidential
CONT3 EGSM
DCS Rx
[Volt] Rx
0 X
0
2.7
0
0
Figure 2: Antenna Switch Test Points
Copyright  2003 Nokia Corporation.
Company Confidential
RF Troubleshooting
PCS Rx EGSM Tx
X
X
X
NEM-4
DCS/PCS
Tx
X
Page 6(b)-81