SQ26-01 Hydrophone

The Sensor Technology SQ26-01 hydrophone is a reliable, low cost, rugged hydrophone which is integrated into instrumentation.

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Sensor Technology SQ26-01 hydrophone Beam Pattern

The SQ26-01 hydrophone is commonly used in towed arrays, AUVs, and autonomous recorders. This hydrophone is very popular with student AUV competition teams.

The usable response (+3/-12dB) is good to better than 50kHz. The official "Flat" frequency response (±1dB) is rated to 28kHz. See the frequency response plots and the beam pattern plots (click on any thumbnail for enlargements).

Although the SQ26-01 hydrophone is low cost, it is a professional hydrophone and is not recommended for novice users.

The SQ26-01 hydrophone has a 2000m depth rating and is, therefore, subject to export restrictions.

  • Sensor Technology SQ26-01 hydrophone
  • SQ26-01 hydrophone receive voltage 100-3000hz
  • Test Frequency: 2-50kHz
  • Beam: 5kHz
  • Beam: 10kHz
  • Beam: 35kHz

SQ26-01 hydrophone specifications
Linear Frequency Range (±1dB) [kHz] .001 to 28
Usable Frequency Range (+3/-12dB) [kHz] 0.001 to > 50
Transducer Voltage Sensitivity @ 20°C [dB, re 1V/µPA] -193.5
Transducer Voltage Sensitivity @ 20°C [V/bar] 20
Transducer Charge Sensitivity @ 20°C [nC/bar] 24
Acceleration Sensitivity [mbar/g] < 0.2 when properly mounted
Maximum Operating Depth [m] down to 2,000
Operating Temperature Range [ °C] -30 to 60
Capacitance (± 10 %) @ 20 °C [nF] 1.4
Sensitivity Variation with Temperature less than 1dB loss from 0 to 35 °C
Capacitance Variation with Temperature 0.33% increase per °C
Capacitance Variation with Depth 7% loss per 1,000 m
Dimensions [mm] 25.4 L x 25.4 dia.
Mass [grams] 16
Electrical Leads two-wire shielded, 28AWG, 30cm (12") long
Shielding integral Faraday cage type
Electrical Insulation [Ω] > 500 M
Water Blocked Leads No

A preamplifier with high input impedance, such as the Reson VP1000 or Reson VP2000 is required in order to achieve a frequency response of 1Hz.


  • Autonomous Recorders
  • Autonomous Underwater Vehicles (AUV)
  • Remotely Operated Vehicles (ROV)
  • Towed Hydrophone Arrays