+44 (0)1262 490234    sales@neptune-sonar.co.uk

Communications » T257

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The Type T257 is one of a series of underwater transducers available from Neptune that are designed for use in transponders, beacons, acoustic release mechanisms and data communication systems. 

The nylon base incorporates threaded fastenings and an 'O' ring seal allowing simple and direct mounting onto equipment or pressure housings. 

The T257 is available with or without acoustic calibration which is traceable to National Standards.

Technical Specification

Resonant Frequency (Nominal)
  • 24 kHz
Useful Frequency Range
  • 16 kHz to 30 kHz
Beam Pattern Horizontal
  • Omni ± 2 dB
Beam Pattern Vertical
  • Toroidal (See Graph)
Transmit Sensitivity
  • 136 dB re 1μPa/V @ 1m
Receive Sensitivity
  • -190 dB re 1V/μPa
Capacitance at 1 kHz (with 10m cable)
  • 12,000 pF
Transmit Voltage (Max)
  • 600 Vrms
Transmit Voltage / Duty Cycle (Max)
  • 600 Vrms @ 10%
  • 180 Vrms @ 100%

Mechanical Specification

Cable Type
  • Ø7mm Polyurethane Jacket, Screened Twisted Pair
Operating Depth
  • 2000m
Cable Length
  • 1m standard
  • (Additional lengths supplied to order)
Weight Air/Water (including 10m cable)
  • 0.78 kg / 0.25 kg
  • Not fitted as standard
  • (Optional Customer Specific)
Operating Temperature
  • -5 to +40 °C
Storage Temperature
  • -40 to +80 °C

Our Company

Formed in 1990, Neptune Sonar is now a leading company in underwater transducer technology, offering one of the world's largest and most comprehensive range of undersea defence and commercial transducers.

Based in the UK, our research and manufacturing operation is located on a 25-acre site in East Yorkshire. With a 60,000 square metre trials lake and a floating calibration laboratory, the site provides an extensive range of facilities supporting every aspect of acoustic transducer development from modelling and design to final product acceptance.

Neptune Sonar Limited
Kelk Lake
East Yorkshire
YO25 8HG

T: 01262 490234
E: sales@neptune-sonar.co.uk
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We design, manufacture and test acoustic sensors and electronics for...

  • Naval Defense
  • Maritime Security
  • Offshore Oil & Gas
  • Hydrographic Survey Industry
  • Oceanographic Science
  • Environmental Sectors
  • Aquaculture