RT 6-1000 Acoustic Release Transponder

The reliable choice to deploy, leave and recover seafloor equipment and sensors
1,000 metre depth rating; twice that of similar low-cost acoustic release transponders
Works with Ranger 2 USBL. Use it to track and activate your RT 6-1000s
>13-month battery life means less time servicing it and more time using it
150 kg Working Load Limit to support your sensors and instruments
Recovering seafloor equipment? Fit the optional rope canister and it will do all the heavy lifting for you

Deploy it. Track it. Locate it. Recover it. RT 6-1000 does it all

Introducing RT 6-1000, our new entry-level acoustic release transponder that comes with features that are far from entry-level. Such as 1,000 metre depth rating, battery life of >13 months, optional rope canister and release mechanism that won’t let you down.

If you’re a scientist, surveyor or in the military, you’ll know how essential an acoustic release transponder is when deploying and recovering seabed equipment and ocean sensors. Reliability, endurance, payload and ease-of-use are all must-have features; everything infact you’ll find that comes as standard in the RT 6-1000.

For a start, it works with our Micro, Mini and Ranger 2 USBL tracking systems. So you can now deploy, track, locate and retrieve your moorings with topside equipment you’ll find installed on hundreds of survey vessels around the world.

If you don’t have access to Ranger 2, no problem. The RT 6-1000 can be setup and controlled via our Android app. All you need is an NFC enabled device and a second RT 6-1000 which stays with you on the surface. For small boat operations, what could be simpler? Soon, you’ll also be able to order a ruggedised over-the-side dunker that’s cable-connected to our deck test unit, iWand.

And talking of moorings, the RT 6-1000 work down at 1,000 metres, twice that of many other release transponders available on the market. As well as going deeper, RT 6-1000 also operates for longer – around 13 months – perfect for year-long surveys so you can deploy it and forget about. When it’s time to recover it to the surface – and the valuable equipment it’s attached to – it’s screw-off release mechanism won’t let you down.

Why RT 6-1000?


  • Medium Frequency (19-34kHz) band.
  • Omni-directional transducer. Track it all the way to the surface
  • Sonardyne Wideband 2 signal architecture supporting over 300 unique addresses. Perfect for very large surveys involving multiple moorings close to each other


  • 450 mm x 65 mm (max dia. 100 mm), 500 grams weight in water
  • Plastic, super duplex stainless steel and anodised aluminium construction. ROHS compliant
  • Field proven screw-off release mechanism
  • NFC for setup using Android app
  • Optional rope canister for lifting heavy items


  • 1,000 m depth rated
  • >13 months battery life; alkaline battery
  • 150 kg Working Load Limit
  • Compatible with Ranger 2 USBL systems
  • Secure and robust two-way acoustic communications. Only release what you want to release


  • What’s in the box: RT 6-1000, shackles, release nuts (x10), manual on USB
  • Warranty: 1 year return to Sonardyne service centre
  • ITAR Controlled: No
  • UK Export License: Not required

More about this product

RT 6-1000 Specifications & DataSheet

Feature Type 8327
Depth Rating 1,000 metres
Operating Frequency MF (19–34 kHz)
Transducer Beam shape Hemispherical
Transmit Source Level (dB re 1 µPa @1 m) 187 dB
Tone Equivalent Energy (TEE)* 193 dB
Receive Threshold (dB re 1 µPa) <100 dB
Working Load Limit (4:1) 150 kg
Proof Load 300 kg
Breaking Load 600 kg
Maximum Safe Release Load 150 kg
Battery Life (Alkaline) >13 months
Inclinometer Accuracy ±5°
Mechanical Construction Plastic, super duplex stainless steel and anodised aluminium alloy
Operating Temperature -5 to 40ºC
Storage Temperature -20 to 55ºC
Maximum Dimensions (Length x Diameter) 514 x 63 mm (20.2 x 2.5”)
Weight in Air/Water** 2.0/0.5 kg

Rope Canister (longer lengths available)

70 metres (250 kg WWL)
120 metres (250 kg WWL)
160 metres (125 kg WWL)


CE Marked to EN-60945, EN-61010

*TEE – WBv2 signals are 2x the duration of Sonardyne tone signals, therefore the TEE figure is to give the user an idea of the operational performance when comparing Wideband and Tone systems.
**Estimated Weights.



To request a manual simply tick the box next to the manual you require and then press the Request Form button. You will then be able to request addition manuals for other products and your request will be emailed to our Customer Support Team who will reply to your enquiry. Alternatively please contact your local office who will be more than happy to help.

User Manual - RT 6-1000

  • Manuals Request


    Spares and Accessories

    Item Description Part number Quantity Required

    • Spares and Accessories


      My NFC device is unable to contact transponder

      If your NFC device cannot contact the transponder it may be due to one of the following reasons:

      The NFC device is not close enough to the transponder or is being held at an incorrect angle – reposition the NFC device next to the transponder. On the RT6 App tap: Advanced > NFC Optimise Tool to determine the best position for the NFC device.

      The NFC device is not working correctly or has locked – Check/restart the NFC device.

      The RT6 App has locked – redstart the RT6 App.

      NFC interface has locked – power cycle the RT 6-1000 by removing the battery and waiting 60 seconds before replacing it.

      The transponder is not replying to interrogation or commands

      An incorrect transponder address is set in the Topside Control – check the address and repeat using the correct address.

      Operating at long range – increase transmit power and receive gain to the surface transceiver (Ranger 2).

      Surface thermocline refracting reply signals – lower transducer below thermocline.

      Noise level at surface transceiver too high – lower the dunking transducer – reduce the surface transceiver gain settings (Ranger 2).

      Transponder battery power low – check battery levels.

      Other acoustic systems maybe operating in the same frequency band.

      No NFC device is available to connect the battery

      If you don’t have an NFC device available, the RT 6-1000 can be enabled by disconnecting the battery for >10 seconds and then reconnecting it.

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