6-5
Analysis of NG Display
CN/NG
NG appears, even if the equipment is operating normally when the satellite signal is weak.
The CPU1 on the CPU board receives C/N data from the DEMOD circuit. If the signal
level is below 31dB, NG appears, indicating that receiver circuit is defective, ocean
region selection is incorrect, or blocking problem exists.
DEMOD
CPU 1
(U49)
CPU 2
(U23)
RX
sig.
RX
sig.
C/N data (8bit)
J10-4
TX
ANT
DIPLEXER
Antenna unit
Communication unit
50kHz
1530 - 1545MHz
RX freq.
offset data
RF CON
VITERBI
(U54)
CPU
To terminal unit
To Next Page
Loading...
