500 SERIES INSTALLATION MANUAL Page 4-21190-00181-02 Rev Q4.9 RMI/OBI4.9.1 RMI/OBI FunctionThe MAIN OBI output provides bearing information from the active waypoint for Bendix/King Serial OBIdevices based upon the 500 Series unit’s GPS navigation. For the GNS 530, the MAIN OBI output may beconfigured so that it sends VOR/ILS bearing information when VLOC is selected by the GNS 530 CDIkey.The VOR OBI output provides bearing information from the active waypoint for Bendix/King Serial OBIdevices based upon the GNS 530 VOR receiver.When a localizer channel is tuned on the VLOC window, there is a bit in the data stream set to indicate thata localizer frequency is tuned which stows the needle or drive it to the 3 o’clock position.4.9.2 RMI/OBI Electrical CharacteristicsPin Name Connector Pin I/OMAIN OBI CLOCK P5001 43 OutMAIN OBI SYNC P5001 45 OutMAIN OBI DATA P5001 44 OutPin Name Connector Pin I/OVOR OBI CLOCK P5006 25 OutVOR OBI SYNC P5006 26 OutVOR OBI DATA P5006 27 OutThe output driver is active low. The driver output voltage is not more than 1.0 V when sinking 20 mAdc.The maximum off state leakage current with respect to ground is less than 10 PAdc.4.9.3 RMI/OBI ConfigurationFor the GNS 530, refer to section 5.2.9 for the MAIN OBI source configuration.4.9.4 RMI/OBI Calibration and CheckoutNone.4.9.5 RMI/OBI InterconnectRefer to Figure F-28 on page F-57 for the RMI/OBI interconnect.
