Table of Contents
Advertisement
NHL-4/4U
Troubleshooting Instructions
7URXEOHVKRRWLQJ GLDJUDP IRU *60 UHFHLYHU
3KRQH LQ ¦&RQWLQXRXV§ PRGH $*& VHWWLQJ ¦§
Apply –90dBm
942.46771MHz signal
from generator to anten-
na connector
Yes
No
Oscilloscope at RX_I
Signal 700mVpp
DC offset 1.35V***
Frequency 67.7kHz
Yes
900RX chain
functional
3DJH
Company confidential
)LJXUH *60 UHFHLYHU WURXEOHVKRRWLQJ
Yes
Change ge-
Spectrumanalyzer
Antenna Switch
nerator level
outputs, GSM900
to –50dBm
–88 dBm
Yes
Spectrumanalyzer
HELGA inputs
GSM900
–89 dBm
Yes
Oscilloscope
VR1,3...6 2.7V
Check HELGA serial
interface
(burst mode)
Spectrumanalyzer
4G VCO out
3769.6MHz
∼–30 dBm (*
Yes
Check HELGA
N500
1RNLD &RUSRUDWLRQ
CCS Technical Documentation
No
No
Spectrumanalyzer
Antenna Switch
input
–84 dBm
Yes
No
Oscilloscope
Oscilloscope :
Check HELGA
VANT_1...3 0V
serial interface
(burst mode)
Yes
Check HELGA
N500
Check Antenna
All spectrumanalyzer reading
switch
values are measured with
Z800
2.5 kohm passive probe (use
tweezers to connect the
probe ground to the nearest
PWB ground). Reading value
No
is represented without
Check L809
+34 dB compensation.
L810
* Spectrumanalyzer
No
Check Base-
reading with 1 kohm
band
passive probe (right val-
ue add +34 dB)
No
Synthesiszer trou-
bleshooting
Check C831,
L811
No
Check Base-
band
Yes
* ** DC–level of RXI/RXQ in
continuous mode will decrease
slowly.
The original level can be resto-
red by rewriting gain set.
,VVXH
Advertisement
Table of Contents
