UPX-14

UPX-14 Long Range Interrogator-Responder IFF/SIF Set - A Long-Range Interrogator-Responder IFF/SIF set built by ?????. The UPX-14 transmits IFF/SIF interrogations and receives replies from aircraft within the host radar's range. The UPX-14 requires a master external encoder and a separate decoder for each operating position/data processor. Typical of the encoder/decoder equipment used in a manual system is the GPA-122 which allows up to 14 decoder units or one for each radar scope. In the SAGE System, the FST-2 Coordinate Data Transmitter supplies the encoder and decoder functions to the UPX-14. It is possible with the UPX-14 to process information about friendly aircraft (SIF) and to determine if an aircraft is friendly (IFF). SIF information is obtained by interrogating friendly aircraft with a set of two pulses, the space between them determines which of the 4 modes is used. IFF (Identification Friend or Foe}) also known as Mode 4 transmits the two pulses and a classified (a/o 1958) encrypted code train of pulses providing identity information. UPX-14 Interrogator-Responder IFF/SIF Mode Int Spacing Reply Codes Users Uses Notes 1 3 us 32 Mil 2-digit 5-bit mission code, cockpit selectable 2 5 us 4096 Mil 4-digit octal unit code set on ground for fighters can be changed in flight by transport aircraft 3A 8 us 4096 Mil/Civ 4-digit octal id code for the aircraft, set in the cockpit assigned by the air traffic controller 3C 21 us 1278 Mil/Civ Altitude from aircraft altimeter 4 Encrypted Challenge 3-pulse reply Mil Encrypted ID info UPX-14 Interrogator-Responder IFF/SIF Element Value Notes Nomenclature UPX-14 Origins UPX-6 Variants Manufacturer Type SIF/IFF Interrogator-Responder Technology Tube IEEE Band UHF Transmit Frequency 1030 MHz Receive Frequency 1090 MHz PRF Host radar determined Range Host radar determined Long Power 117 V, single phase 50, 60, 400 Cycles Coder/Decoder External UPX-14 Controls. See Also: US IFF/SIF Sets Sources: Winkler, David F., Searching the Skies: the Legacy of the United States Cold War Defense Radar Program, USAF Hq Air Combat Command, 1997, 192 pages, Pdf MIL-HDBK-162A, 15 Dec 1965. CDC 30372, Extension Course Institute Air University, Aircraft Control and Warning Tecnician (AFSC 30372) Vol 3, AC&W Equipment, Part II, page 70-122 Available from Google Books. Links: