Earth Observation System
3. Troubleshooting
3.1 Abnormal condition
The section descries the abnormal conditions and troubleshooting of troubles in the receiving
subsystem as well as associate with other subsystem. To find and handle troubles in each
equipment, refer to relevant pages of the manual for each equipment.
Abnormal condition
No image output on the quick looks equipment after a passage of the satellite arrival time.
<Assumption>
The antenna is oriented to the arriving satellite, the programmed tracking operation normal and
the predicted value for the orbit correct.
Figure 3 Flow chart for Troubleshooting
3.2 Abnormal condition 2
The satellite reception is performed normally but the operation fails with a testing equipment.
Figure 3 Flow chart for Troubleshooting
3.4 Measure in case of trouble
When a trouble is detected the instructions below:
- Turn off the power of the equipment in trouble installed in the antenna center ring; The
D/C and U/C should be powered off at the main receiver.
- Inspect the equipment in trouble according to the maintenance manual for that
equipment, and notify NEC of the details of the trouble.
Level control
Proposes of the Test
To confirm the control function of output level
Performance objective
(a) Control by means of the step attenuator.
(b) Remote control can be performed at the operation room.
(c) Output level
Range: -110 dBm (1 dB step).(This level is calculated on condition that the test RF signal is
supplied to 8 GHz Band Low noise Amplifier input terminal.)
Setting: The deviation is less than 2-dB accuracy
(d) Test Equipment
signal generator : HP– 8863 A
Power meter : HP- 436 A
Controller in the 8 GHz band main receiver
