
4 (5)
Uppgjord (även faktaansvarig om annan) -
Prepared (also subject responsible if other)
Nr -
No.
SES/KTR Mats Andersson
KTR97:2486
Dokansv/Godk -
Doc respons/Approved
Kontr -
Checked
Datum -
Date
Rev
File
KTR M. Andersson
1997-12-07
A
97-2486-FAULT TRACING F800.doc
3.5
LOW SENSITIVITY OR POOR AUDIO QUALITY
Step Check
Likely fault(s)
1
Connect the test handset to
the transceiver unit and
connect the RF test set to
the station’s antenna
output. Set up the test set
for receiver testing. Set the
switches on the test
handset for external audio
sources and connect the
RX line signal from the
handset to the RF test set.
Apply an on-frequency
signal to the station and
measure the sensitivity
(SINAD).
Low sensitivity:
1. Transceiver unit
2. Internal RF cabling
3. Built-in filters, if any.
Normal sensitivity:
1. Line panel
2. Interconnection board
3.6
NO COMMUNICATION WITH REMOTE CONTROLLER/RADIO EXCHANGE
Step Check
Likely fault(s)
1
Check that the green led
indicating 12VDC on the
interconnection board is lit.
1. Power supply
2. Transceiver unit
2
Check status indications on
the line panel.
Refer the service manual for the
concerned line panel for
information.
3.7
VOLTAGE CHECK
The transceiver unit pr12V and +5V to external units such as the line
panel and the interconnection board. The transceiver unit includes fuses for
+12V supply. The fuses are located on the transceiver’s radio board. The
fuses are of SMD type.
+12VDC
Transceiver unit P405:1
Interconnect board P2:6, J2:A11, J1:A31, J1:B31 and P8:6
+5VDC
Transceiver unit P405:13
Interconnection board P2:8, J1:A32