190-00906-01 GTX 23 Installation ManualRev. C Page 1-91.10 Operating InstructionsThe GTX 23 is a remote-mount LRU with no user controls or indicators. All user interface is accomplishedthrough a compatible display device. Although different displays will handle the transponder interfacedifferently, all will typically have the following user inputs:Mode Selection:1. Standby Mode: In Standby Mode, the GTX 23 will not reply to interrogations.2. ON Mode: In ON mode, the GTX 23 will generate Mode A and Mode S replies, but Mode C altitudereporting is inhibited.3. Altitude Mode: In Altitude Mode, Mode C altitude reporting is enabled.Code Selection:1. Entering a Code: A total of 4096 discrete identification codes can be entered.2. VFR Code: Selecting VFR changes the Code to the pre-programmed VFR code.Ident Function:Selecting the Ident function sends an ID indication to ATC for 18 seconds. This ID indication distinguishesyour transponder from all others on the air traffic controller’s radar screen.NOTEFor detailed operating instructions, refer to the pilot’s guide for the equipment thatprovides the GTX 23 user interface. The G3X Pilot’s guide (190-01115-00) providesinformation for operating a GTX 23 in a G3X system.1.11 Reference DocumentsThe following publications are sources of additional information for installing the GTX 23. Beforeinstalling the unit, the technician should read all relevant referenced materials along with this manual.Table 1-7 Reference DocumentsPart Number Document190-01115-01 G3X Installation Manual
