Power for the MFT-1 multi-frequency transponder is supplied by two standard alkaline 9-volt batteries which last for many months. For longer durations, lithium batteries can be used. Larger housings are also available which hold more batteries greatly increasing the operating time.

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The quick and easy way to relocate an underwater site

JW Fishers acoustic sonar transponder makes it quick and easy to relocate an underwater site or piece of equipment. The sonar transponder is attached to an underwater location where it sits quietly listening for a coded signal from an acoustic sonar interrogator. When a diver, equipped with a sonar interrogator, points the interrogator in the direction of the transponder, the transponder sends out a coded return signal that is picked up by the acoustic sonar interrogator. The interrogator displays the distance to the transponder (in feet or meters), and a compass displays the heading to the transponder. The diver can follow the signal directly to the target. The acoustic sonar transponder can transmit any one of sixty (60) different frequencies (operator selectable), so many can be deployed in the same general area without interfering with each other. The diver sets the acoustic sonar interrogator to the frequency of the acoustic transponder and is guided directly to it. The JW Fisher MFT-1 multi-frequency transponder has a range of over 3,000 feet.

The standard frequencies are 20kHz to 50kHz in 500Hz steps (special frequencies are also available). The JW Fisher MFT-1 Transporter can be automatically activated when put in the water or manually activated with a switch before deployment. Many MFT-1 can be deployed in the same general area, each transmitting a different frequency. A diver using the DHI-1 diver-held interrogator can pinpoint the exact location of each MFT-1 transponder.

The Extended Operation Housing holds six batteries and gives 3 times the normal operating time. The Very Long Duration Housing holds twelve “D” size batteries and gives 12 times the normal operating time.

All JW Fisher’s acoustic sonar transponders are covered by a full TWO YEAR WARRANTY.

  • Custom frequencies (other than 20kHz to 50kHz in 500Hz steps) are available: $95
  • Carrying case (holds up to four MFT-1 or two MFT-1 and a DHI-1): $250
  • Extended Housing (3 times normal operating time): $195
  • Very Long Duration Housing (12 times normal operating time): $785

Relocating Underwater Sites Easy With Acoustic Beacons


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Additional information

Weight 9 lbs


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