Research Concepts RC2000C User Manual
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RC2000C Az/El Tracking Antenna Controller
Chapter 4
Inclined Orbit Satellites
Research Concepts, Inc. • 5420 Martindale Road • Shawnee, Kansas • 66218-9680 • USA
www.researchconcepts.com
4. 'IS THIS AN INCLINED ORBIT SAT'. Hit the YES key in response to this question.
5. 'ENTER SAT LON LLL.L'. Use the number keys and the decimal point to enter the numeric portion
of the satellite longitude; i.e., if the longitude is 100.5 West, key in '100.5'. Terminate the entry of
the numeric portion of the satellite longitude by hitting the ENTER key. The BKSP key may be used
to backspace over any incorrectly entered data any time before the ENTER key is pressed.
The user is next prompted to enter the direction associated with the longitude entry. Hit the 4 key to
specify an East longitude, and hit the 6 key for a West longitude. Hit the ENTER key to terminate
the entry.
6. 'SELECT BAND 0-C,1-K,2-C&K,3-L'. If the satellite is a hybrid which has both C and Ku band
transponders, select 2. Otherwise, key in the appropriate band designation.
7. 'SAT INCLINATION (2-16 DEG):' See the Appendices for a list of inclined orbit satellites and a
nomograph which may be used to determine the inclination of the satellite's orbital plane to the
earth's equatorial plane. Key in the appropriate value, followed by ENTER. Note that very few
communications satellites have an inclination greater than 6 degrees. If you are unsure of the
satellite inclination, try 5 degrees.
8. The user is next prompted to specify the horizontal and vertical polarization values for the satellite.
Use the CW and CCW keys to skew the polarization, and the H and V keys to set the polarization.
(Values must be specified for the horizontal and vertical polarizations even if the antenna has no
polarization adjustment. If the antenna has no polarization adjustment, make sure that the Rotating
Feed Present CONFIG mode item is set to NO. The controller will then assume that a polarotor is
connected to the antenna. A polarotor is controlled in an open loop fashion, i.e. the controller sends
control signals to the polarotor and does not receive any feedback from the polarotor - the controller
cannot tell whether a polarotor is present or not.) NOTE: For feeds that can simultaneously receive
both H and V polarization both ‘H’ and ‘V’ polarization values should be the same. Make sure that
both values are peaked up on different transponders. ANOTHER NOTE: Not all versions of the
software support polarization control.
9. 'INITIAL TRACK POL (H OR V)?' Press the appropriate key for the polarization of the initial track.
Note that not all versions of the software support polarization control.
10. Control will transfer to TRACK mode. 'TRAK' will be displayed in the upper right hand corner of the
display. If the user designated a hybrid satellite (both C and Ku band), the following prompt
appears: 'BAND? 0-C 1-K:'. Select the appropriate band. The band designation for a hybrid
satellite may be changed via the TRACK menu. The band that the controller assumes is active is
displayed in the upper right hand corner of the display just to the right of the 'TRAK' banner.
11. 'INITIALIZING - PLEASE WAIT' will appear, then the controller will switch to STEP TRACK sub-
mode. The controller will STEP TRACK for 23 hours, 56 minutes, and 4 seconds while building up
the program track table. When program track data is available for the current sidereal time, control
will transfer to the PROGRAM TRACK sub-mode. If the satellite transponder goes down while step
tracking, the controller will switch to SEARCH mode and attempt to require the satellite.
12. A number of errors can be detected during the TRACK mode initialization process. The SCALE
FACTOR error indicates that the Azim Constant CONFIG mode item is set to zero and two
geostationary satellites with sufficient spacing are not available which allow the azimuth scale factor
to be derived. The SYSTEM error indicates that an alarm message is flashing on the bottom row of
the display.
13. If the Search Enable CONFIG mode item is enabled, a good test of the tracking system is to exit
TRACK mode by depressing the MODE key, and then selecting the satellite via AUTO mode to
reacquire the satellite. AUTO mode will prompt for the desired polarization and transfer control to
the SEARCH sub-mode of TRACK mode. A search will be performed and when the satellite is
found, STEP tracking will resume. Note that not all versions of the software support polarization
control.