Key Facts
Picture R&S®GB127S Antenna Control Unit

The R&S® GB127S has three control outputs on its rear panel to control external units:

  • One I²C bus control output comprising an I²C bus interface, the +28 V DC supply and GND, for connecting an R&S® RD127, an R&S® ZS129A2 or an R&S® ZS129A5 (to control one 1-out-of-n switch)
  • Two identical open collector control outputs comprising each eight independent control lines, the +28 V DC supply and GND, for connecting an R&S® ZS129A5 (to control up to eight 1-out-of-2 switches or one 1-out-of-6 switch and two 1-out-of-2 switches or one 1-out-of-8switch) or max. eight R&S® ZS127Z1

The functionality of the system can thus be enhanced without a second control unit being required.

If several units are connected, you must bear in mind that the maximum supply current is 1.8 A.

The basic firmware of the R&S® GB127S is identical for each unit. Customer and system-specific information is defined and stored on a chipcard.

If the antenna control unit is delivered as part of a complete monitoring system, the chipcard will usually be programmed to the system-specific configuration by Rohde & Schwarz.

However, programming may also be performed by the customer. A null modem cable connected to the R&S® GB127S and the R&S® GB127x Card Editor, which runs under Windows XP, Windows 2000 or Windows NT4.0, are required to read from and write to the chipcard.

When the chipcard is inserted into the chipcard reader, the Antenna Control Unit R&S® GB127S is configured automatically for the system in question.

The following information is stored on the chipcard:

  • R&S® RD127 control enabled/disabled
  • Rotator type and configuration
  • Number of serial interfaces in use
  • Function of each serial interface in use
  • Commands used for rotator control
  • Function of the commands for the control outputs and antenna switches
  • Text to be output on the display