Products

Navigational Beacons: AN/URN-25 NAVY TACAN TRANSPONDER

This AN/URN-25 TACAN Transponder Group is a full service transponder, which provides TACAN-equipped aircraft with range, bearing, and identification within a 300 mile radius, when coupled with a suitable antenna, DIVIE equipped users are provided range information within the same radius.

The transponder has 252-channel capability, transmits 3kW peak power. has built-in monitor and test capability and is completely solid state with the exception of redundant ceramic triodes utilized in the transmitter, The unit drives all existing mechanically rotated TACAN antennae and has been designed specifically for the state-of-the-art electronically modulated antenna groups.

The modern design of the transponder includes modular construction, the use of digital techniques, emergency mods operations at reduced power, or automatic switchover in dual installations, in the event of a failure. Among the beacons many features is included a 1 minute channel change capability.

The AN/URN-25, sponsored by the U.S. Navy, Naval Electronic Systems Command, is designed to military specifications, requiring full qualification for installation in surface ships. transportable vans, and fixed station sites. The beacon employs the some reliable techniques and knowledge developed during NevCom's 25 years of TACAN design and production efforts. It is the only modern, high power system to have received U.S. Military Service approval and is currently in its fourth production build cycle.

FEATURES

• All solid state. (redundant ceramic triodes in the transmitter.
• All band capability X and Y mode, 252 channels.
• 3kW peak power,
• Channel changing time, less than I minute. (average).
• Monitors, meters and test circuits are built-in; external equipment is not required.
• Ease of maintenance due to modular construction, MTTR of 26 minutes,
• Use of digital techniques to eliminate complex adjustments.
• High reliability, MTSF of 6000 hours.
• Provisions for single or dual installations, Automatic switch over capability in dual installations,
• Beacon cabinets identical in single or dual installations.
• Emergency mode transmission capability in the event of transmitter tube failures.
• Status Control indicator provides remote control over telephone lines.
• Reduced power output mode (700 watts).

PHYSICAL DESCRIPTION

• Power
  115 Volts 45Hz to 450 Hz
• Weight
  Transponder: 960 lbs (436 kg)
  Status Control Indicator: 75 lbs (34 kg)

PERFORMANCE CHARACTERISTICS

TRANSMITTER

• Power Output
  3000 watts (at and of tube life)
  700 watts (selectable mode)
• Emergency Power Levels
  700 watts and 160 watts

PULSE

• Shape (in accordance with MIL-STD-291)
• Squitter Distribution(in accordance with MIL-STD-291)
• Reference Groups(in accordance with MIL-STD-291)
• RF Pulse Spectrum
  Energy Levels: (SDO kHz bands)
  800 kHz from Center Frequency 200 mW
  2 MHz from Center Frequency 2 mW
• Pulse Count Output
  Adjustable from 2700 to 4000 pulse pairs per second
• Tone
  Three letters plus one number selectable
  Tone repeats every 30 seconds

RECEIVER

• Receiver Sensitivity to 60% efficiency, -92 dBm
• Bandwidth
  Less than 3 dB loss of sensitivity with an incoming frequency drift of 1100 kHz
• Selectivity
  80 dB rejection ±900 kHz from center frequency
  66 dB rejection all other frequencies 960 - 1215 MHz
• Response Delay Accuracy
  Delay Variation: ±0.5 µs, +0. 25 µs, ±0.8 µs
  Input Signal Strength: 0 dBm to -10 dBm, -10 dBm to -70 dBm, -70 dBm to -90 dBm
• Dead Time
  60 ±1 µs X channels
  66 ±1 µs Y channels
• Echo Suppression
  Adjustable 10 to 40 dB above
  threshold 150 to 400 µs duration
• CW Interference
  Respond to signals 10 dB above the cw level
• Narrow Pulse Interference
  No loss of traffic handling capability. with single
  pulses or pulse pairs 1.2 µs or less

BEACON TEST GENERATOR

• Frequency synthesizer variable in 100 kHz steps
• Variable attenuator 0 to 100 dB
• Pulse modulation 40 to 4000 pulse pairs/second
• Variable pulse spacing 10 µs to 40 µs
• Fixed pulse spacings of: 10; 12; 14; 34; 36; and 38 µs

RELIABILITY

• MTBF of 6000 hours-shipboard
  18000 hours-Ground Station

MAINTAINABILITY

• Mean corrective maintenance time:
  25 min to module
  120 min to piece parts

MONITORED PARAMETERS

Receiver sensitivity
ID period
Continuous ID
Pulse spacing
Duty cycle
Reply delay
AC line
Antenna
Cavity temperature (anode face)
Spectrum control
Illegal channel
Synthesizer Status
Monitor inhibit
Burst

8400 Lakeview Parkway, Suite 200
Pleasant Prairie, WI 53158
262-947-8400
Fax 262-947-8403

info@targetcorporation.com