Setting Azimuth And Elevation Limits; Motor Drive Polarity; Setting Limits - RESEARCH CONCEPTS RC2000A DUAL AXIS Instructions Manual

Antenna controller

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RC2000A Dual Axis Antenna Controller

polarization alarm is active, an error message will flash on the bottom row of the display and the

polarization drive will be disabled. The alarm can be de-activated via RESET mode.

5. Once the polarity of the motor drive and sense lines have been verified, the polarization limits may

be set. This is done from the POL LIMITS mode. To set the limits, the user positions the

polarization motor at each limit (through the use of the CW and CCW keys) and hits the 5 key. Note

that in POL LIMITS mode there are no restrictions on polarization motor movement. It is

recommended that an assistant be stationed at the antenna to ensure that the polarization motor's

(or sensor's) mechanical limits are not exceeded. Damage to the antenna feed, polarization motor,

or sensor may occur if the limits are exceeded.

6. This section describes how to enable and calibrate the angle display of polarization position. Angle

display is enabled by setting the CONFIG mode 'Pol Angle Display' item to 1.

To calibrate the angle display, the user must initialize the CONFIG mode 'POL DISPLAY 0 DEG CNT'

and 'POL DISPLAY 90 DEG CNT' items. The position entered at the 'POL DISPLAY 0 DEG CNT' will

display 0.0 degrees and the position entered at the 'POL DISPLAY 90 DEG CNT' prompt will display as

90.0 degrees. All intermediate positions are scaled appropriately. The maximum possible range of

displayed angles is from -99.9 degrees to 999.9 degrees.

It is not necessary to enable and calibrate the angle display at this time. These CONFIG mode items

may be initialized after some satellites have been entered into the controller's non-volatile memory.

3.4

The next step in the installation procedure is to ensure that the polarity of the motor drive wiring is

correct, the position sensors and polarotor function properly, and then to set the azimuth and elevation

limits. All of the operations outlined in this section can be carried out with the controller in LIMITS

mode.

IN LIMITS MODE THE USER HAS UNRESTRICTED MOVEMENT OF THE ANTENNA, THERE ARE

NO SOFTWARE AZIMUTH OR ELEVATION LIMITS, AND ANTENNA JAMMED SENSING DOES

NOT TAKE PLACE. WHEN MOVING THE ANTENNA IN LIMITS MODE AN ASSISTANT SHOULD

BE STATIONED AT THE ANTENNA TO INSURE THAT THE ANTENNA DOES NOT MOVE PAST A

PHYSICAL LIMIT. NOTE ALSO THAT THE CW AND CCW POLARIZATION ADJUSTMENT KEYS

ARE ACTIVE.

3.4.1

Motor Drive Polarity

The polarity of the azimuth motor drive is checked by depressing the AZ CCW (AZ CW) ARROW key

and verifying that the antenna moves in the proper direction. The sense of azimuth movement is

defined as seen by an observer located above the antenna looking down on the antenna. If the

antenna does not move in the proper direction, connector J2 pins 4 and 6 need to be reversed. The

polarity of the elevation motor drive is checked in a similar fashion. The UP ARROW key corresponds

to up elevation movement.

The azimuth and elevation position sensor operation can be checked by jogging the antenna about the

appropriate axis and verifying that the position count changes for that axis. Note that the position count

will always decrease for azimuth counter-clockwise and down movement, and will always increase for

azimuth clockwise and up movement. Also the count will not decrement lower than 1 or increment

higher than 65535.

Polarotor operation is checked by using the POL CW and POL CCW keys to skew the polarization.

3.4.2

Setting Limits

The azimuth counter-clockwise and/or down limits are set first. The bottom row of the display prompts

the user to set the limits for each axis. To set a limit, position the antenna at the desired limit, and hit

either the 7 key to set an azimuth limit or the 9 key to set an elevation limit. When the counter-

clockwise azimuth limit or down elevation limit is set, the position count for the axis is reset to 30. The

Research Concepts, Inc. • 5420 Martindale Road • Shawnee, Kansas • 66218-9680 • USA

Chapter 3