Research Concepts RC2000A - Manual (Page 115)

RC2000A Dual Axis Antenna Controller Appendix I 2.6x Addendum 115
4.4.3 RC2000 Non Volatile Memory Satellite Data Polarization Position Fields
Satellite data is stored into the RC2000A’s non-volatile memory via the the controller’s SETUP mode.
When the Pol Control? CONFIG mode item is set to something other than None, SETUP mode prompts
the user to specify the band (C, Ku, or hybrid C and Ku) of each satellite stored in non-volatile memory.
Each satellite data entry contains two polarization position values. One normally holds the horizontal
polarization position and the other the vertical polarization position.
If the antenna is equipped with a two port feed and the user specifies either a C band satellite or a Ku
band satellite (i.e. not a hybrid satellite) the user will only be prompted to supply a single polarization
position. For this case, the polarization position supplied by the user is copied to both polarization
positions associated with the satellite data entry.
If the antenna is equipped with a two port feed and the user specifies a hybrid satellite, SETUP mode
prompts the user to specify whether or not he or she wishes to specify unique C and Ku band
polarization values. If the user opts to provide unique C and Ku band polarization values the C band
polarization position is stored in the location commonly employed to store the horizontal polarization
position. The Ku band polarization position is stored in the location normally used to store the vertical
polarization position.
4.4.4 Polarization Code Display
Previous versions of the RC2000 displayed ‘H’, ‘h’, ‘V’, or ‘v’ to indicate the present polarization position.
To do this the RC2000 keeps track of the satellite data entry in non-volatile memory that is closest to
the current antenna az/el position. The polarization position values associated with this ‘closest
satellite’ are compared to the current polarization position. If the current polarization position is very
close to the horizontal polarization position of the satellite data entry of the ‘closest satellite’ an ‘H’ is
displayed. If the current polarizaiton position is somewhat close to the horizontal position of the closest
satellite ‘h’ is displayed. Similarly for display of ‘V’ and ‘v’.
With introduction of support for a Two Port feed, the pol code display scheme described above was
modified in the following manner when the user has specified that the antenna is equipped with a two
port feed …
If the ‘closest satellite’ is specified to be either a C band or Ku band satellite (i.e. not a hybrid satellite),
the polarization code displayed will be either ‘X’ or ‘x’. For this case both the ‘horizontal’ polarization
field and the ‘vertical’ polarization field associated with the satellite’s entry in non-volatile memory will
contain identical values. If the current polarization position is very close to the polarization positions
stored in non-volatile memory an ‘X’ will be displayed. Somewhat close and an ‘x’ is displayed.
If the closest satellite is a hybrid satellite (both C and Ku band) and the two polarization positions
associated with the satellite’s data entry in non-volatile memory are THE SAME, the displayed
polarization codes will again be ‘X’ or ‘x’.
If the closest satellite is a hybrid satellite (both C and Ku band) and the two polarization positions
associated with the satellite’s data entry in non-volatile memory are DIFFERENT the displayed
polarization codes will again be ‘C’, ‘c’, ‘K’, or ‘k’.
4.4.5 AutoPol Disabled for Dual Port Feeds
The RC2000A supports a feature called AutoPol. The AutoPol system slaves the RC2000A’s
polarization control output to a digital input to the controller. AutoPol is commonly enabled when the
antenna is equipped with a polarotor servo type polarization control device. Many analog receivers
provide provide an output for an H/V select relay. This output can often be tied directly to the RC2000’s
AutoPol Input. As the user selects satellite transponders with the receiver the controller commands the
polarotor to the H/V values corresponding to the satellite that was the last target of an auto move (or the
closest satellite if the antenna has been jogged since the last auto move). The AutoPol Enable and
AutoPol Vpol Level CONFIG items enable and configure the system.
With version 2.6x of the RC2000A software, the behavior of the AutoPol system was modified. With
version 2.6x, if the Pol Control? CONFIG mode items is set to Two Port the AutoPol system is disabled
regardless of the state of the controller’s AutoPol Enable flag. Note that previous versions of the
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