Sea Tel ST88-21 C/Ku-Band TVRO, Installation And Operation Manual

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Maintenance and Troubleshooting ST88-21 C/Ku-Band TVRO
13-14
•
Cross-Level Axis physically moved CCW (down to the left.) and then CW (up to the right.)
Elevation Axis physically moved CW. (reflector slightly pushed up) and then physically moved CCW.
(reflector slightly pushed down.) At the end of chart recording shows
•
DishScan® Drive turned Off, notice the lack of accumulated IVC errors.
13.7.5. Reference Sensor Testing
The ACU provides a means for monitoring the output of the 3 solid state rate sensors and the 3 reference
sensors for diagnostic purposes. The rate sensors and reference sensors are the primary inputs to the PCU for
stabilization.
1. To view the reference sensors, select the REMOTE COMMAND window on the ACU:
2. Using the
LEFT/RIGHT
and
UP/DOWN
arrow keys set the Remote Command value to "
v0000
"
(the v must be lower case) and press
ENTER
.
3. Press
ENTER
key once more to display the
REMOTE MONITOR
window. The lower display will
show "v" and three 4 digit decimal numbers (
v 1111 2222 3333
).
The numbers represent the Cross Level and Level Tilt Sensor outputs and the azimuth encoder respectively.
The Cross Level Tilt display should be 2048 when the level cage is level. It should decrease when the antenna
is tilted to the left and increase when tilted to the right.
The Level tilt display should be 2048 when the level cage is level. It should decrease when the antenna is
tilted forward (EL down) and increase when tilted back (EL up).
The Encoder display will show 2048 in the center of the mechanical range (Relative 360.0), decrease in value
as the antenna is rotated counter-clockwise (down to about 0102 at lower stop) and increase in value as the
antenna is rotated clockwise (up to about 3994 at upper stop).