Picture of product RT-1909/APX-121

Part #: 832100

Model: RT-1909/APX-121




IFF Transponder

Part Number :





  • AN/APX-121 Diversity Transponder incorporates Modes 1, 2, 3/A, C, S, 4, 5 and ADS-B (out)
  • Designed to survive and operate safely in aviation, land and marine environments
  • Continuously operates in harsh uninhabited environments
  • APX-121 includes advanced microwave digital design features that fully support organic
  • BIT/BITE 99% Fault Detection, 90% Isolation to One SRU, 95% Isolation to Two SRUs
  • Designed to replace older IFF transponders, including the APX-100
  • Support of existing KIT-1 or a removable KIV-77 supporting Modes 4 and 5
  • Mode S Elementary (ELS)
  • Enhanced (EHS) operation



Decoder/ Encoder: Modes 1, 2, 3/A, C, S (ELS), Modes 4 & 5, ADS-B (out) Receiver: Solid State, Dual-channel Superheterodyne, 1,030 ± 0.5 MHz Frequency, Bandwidth:-3 dB points, 7.0 to 10 MHz, -40 dB points, ±12 MHz, -90 dB points, ±22 MHz
Transmitter: Solid State 1,090 ± 0.01 MHz Frequency, Reply Rates: 1,200 Hz - SIF Modes, 1,000 Hz - Modes 4, Output is protected against all mismatch 1 dB Droop Interfaces: MIL-STD-1553B, ARINC 429, RS 485, Discrete
Environmental: 70,000 ft Altitude, -40 C to +71 C Reliability: 4,000 hrs MTBF
Design Specs: STANAG 4193, RTCA/DO-181E, DoD AIMS 03-1000A, DoD AIMS 04-900, MIL-E-5400T, MIL-STD-704T, MIL-STD-810, MIL-STD-454, MIL-STD-1686, MIL-STD-1472, MIL-STD-461/2/4 BIT /BITE: Passive Monitoring: Power, SWR, Pulse-Width, Active RF Testing: Sensitivity, Diversity Operation, Decoder / Encoder, Power, SWR, Pulse -Width, 
Dimensions with Applique: Width 5.33 in (13.54cm), Height 5.43 in (13.79 cm), Depth 8.55 (21.7 cm) Power with Applique: 16-30 VDC, 50 Watts Nominal, 60 Watts Max.
Part Number: Description:
832100 IFF Diversity Transponder


- IFF Transponder
Price Condition Status

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