Antenna Products’ azimuth positioners are designed to rotate directional antennas to a desired heading using a remote or local controller. The direction of the antenna can be set in 30 degree segments with a step controller or at any azimuth heading using a synchro control.
The rotators are used in a wide variety of hostile environments and have rugged gear drives to handle high inertial loads. The rotators are designed to mount on a wide variety of towers. Reliability and low maintenance are important features of our rotator systems.
Antenna Products’ rotator designs accommodate large HF log periodic antennas which impose tremendous horizontal and vertical loads when subjected to the maximum-rated wind speed and ice loading. Some rotator models have microcomputers which give continuous updates of status and can accept commands to seek a new azimuth heading via land lines, radio link or RS-232 interface.
Antenna Products manufactures three types of remote control units: step controllers, synchro controller, and computer controllers.
A step controller utilizes a rotary switch to provide 12 cardinal headings that are selectable from the remote control. The twelve headings are equally spaced in azimuth. Once a heading is selected, the drive system automatically positions the antenna to the desired position. A local/remote control switch is provided on the local control at the base of the antenna to permit local selection of azimuth heading and also provides a remote override function to prevent remote rotation during antenna maintenance activities.
A synchro controller uses a transmit synchro in the rotator and a receive synchro in the remote control to indicate the antenna bearing. The operator energizes the drive system at the remote control unit to steer the antenna to the desired heading. Units are available that provide for an additional synchro at the base of the antenna to indicate the heading from the local controller.
The computer controller operates on rotators that use a synchro for positional information.The synchro signal is converted to a digital signal and compared to a digital rotate command. Any difference between position and command closes a contact on an optical output coupler to operate a rotator motor contactor to drive the antenna in either a CW or CCW direction. When the antenna reaches the commanded azimuth bearing, the output coupler opens and rotation stops. The computer interface is user selectable RS-232 or RS-422 serial. Each controller unit is separately addressable, allowing several antennas to be controlled by one computer. The computer may be hardwired to the controllers or may be employ modems and telephones lines.
Two types of computer controls are available. One type is designed for use with antennas that use rotary joints and therefore have no rotational limits, this unit will command movement in the direction of least rotation. The other type of unit has provisions for limit signals and will command rotation to a new heading in the direction that is not impeded by a limit. Both units are provided with an interlock so that control of the antenna may be denied by a switch in the local control at the antenna. Both units may be operated by a keypad on the front panel of the controller. Both units mount in a standard 19 inch rack and require 5.25 inches of panel height. Please contact Antenna Products for further information and proper selection of a controller for your requirements.