User Guide

PAMS
Technical Documentation
NME–3
Troubleshooting
Page 19
Issue 1 10/99
Receiver faults
This section gives an overview of the strategies used to hunt failures and
defects in the receiver path of the radio unit. Tracking of receiver errors is
best done by following the RX signal path and tracking the signal applied
to the antenna port with a probe and a spectrum analyzer. The following
steps should be done prior to the signal tracking:
– Apply test signal generated by CMD55 to antenna port.
Frequency: 947 MHz
Level: –55dBm
– Set radio unit to local mode with Wintesla.
– Choose RF Controls from Wintesla Testing menu.
– Perform the following settings:
Set RX continuous mode
Set Cont. mode channel 60
Tick front end on.
The test signal should then be tracked through the rx signal path by fol-
lowing the procedures given in the figures below.
The RF levels given in the following flow charts were measured with a
Hewlett Packard RF probe. When measuring the levels with a different
probe the resulting levels may be different. The most important thing to
check is wether there is a signal present or not.