37.5kHz – 90 Day Marine Beacon

Building on over 50 years of underwater acoustic beacon manufacturing experience, Dukane Seacom has developed DKM502/90 which is the newest version of the IMO standard in underwater acoustic locating beacons for maritime use. Expanding on the proven reliability of the DKM502, the DKM502/90 will assist in location of VDR & S-VDR capsules up to 6096 meters or 20,000 ft. water depth.

 The DKM502/90 will provide a minimum of 90 days of uninterrupted operation once activated, complying with minimum standard specification SAE8045A, IEC61996-1 & IEC-61996-2.& BSH approved

Physical Characteristics

  • Watertight aluminum case (1.3”dia, 3.99” length (less mount)).
  • Capable of operation at depths of up to 20,000 feet (6096 m)
  • Detectable at a range of 2000 to 4000yards (1800 to 3600 meters) based on environmental factors.
  • Sustained pressure up to 8700 psi.
  • Dual water switch actuation initiates beacon operation upon immersion in either fresh or salt water.
  • The battery used to power the DKM502/90 will sustain beacon operation for a minimum of 90 days at an acoustic output of 160 dB. Operating frequency is 37.5 kHz.

Standard Features

  • Military grade corrosion protection.
  • Chemical coating systems MIL-A-8625
  • Innovative engineering technology that protects against inadvertent actuations.
  • ATS-270M Portable Test Set shall be used to perform operational tests on the beacon.
  • It can be detected at a range of 2000 to 4000 yards with DSL-375 locator.

Beacon Specifications

Operating Frequency:
37.5 kHz ± 1 kHz
Operating Depth:
Surface to 20,000 feet (6096 meters)
Pulse Length:
9.0 milliseconds Minimum
Pulse Repetition Rate:
Not less than 0.9 Pulse/Sec
Operating Life:
90 Days (Minimum)
Battery Life In Beacon:
3 Years
Acoustic Output, Initial:
1060 dynes/cm2 Rms pressure at 1 meter (160.5dB)
Acoustic Output After 90 Days:
700 dynes/cm2 Rms pressure at 1 meter (157.0dB)
Operating Temperature Range:
+28°F (-2.2°C) to +100°F (+37.8°C)
Fresh or salt water
Radiation Pattern:
Rated output over 80 percent of sphere
1.30 inches (3.30 cm) diameter x 3.99 inches (10.13 cm) long (less mount)
Weight, Beacon:
6.7 ounces (190 grams)
Weight, N30A26 Mount:
6 ounces (170 grams)
Storage Temperature Range:
-67°F (-55°C) to 185°F (85°C)