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RT 6-1000

Acoustic release transponder

Engineered for: Seabed, Structure

Deploy it. Track it. Locate it. Recover it. RT 6-1000 does it all. Our new entry-level acoustic release transponder has features that are far from entry-level. Such as 1,000 metre depth rating, battery life of over a year and release mechanism that won't let you down.

At a glance

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

Tested, loaded, commanded and released using Deck Topside

Also works with any Ranger 2 USBL to track it and activate it

>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, moor and recover equipment

Want to know more?

RT 6s work in the MF band so compatible with our family of Ranger 2 USBLs

Dock Topside is IP67 rated so you use it from any type of boat and for up to 8 hours

RT 6-1000s use a highly reliable, screw-off release mechanism proven over many years

Daylight-readable touchscreen with additional physical buttons for release and initiation sequences

Benefits of RT 6-1000 for your operations


There's a range of ways to command your transponder; Deck Topside, Android app, or any Ranger 2 USBL; Micro, Mini and Standard.


RT 6-1000 is more than just an acoustic release. It can be tracked with a Sonardyne USBL system making relocating and recovering it fast and simple.

Deep and heavy

RT 6-1000s are depth rated to 1,000 m and have a 150 kg WLL - deeper and heavier than the Sonardyne LRTs they supersede.


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 you’ll find that comes as standard in the RT 6-1000.

For a start, it works with our family of 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’s NFC capability means that it can be set up and controlled via our Android app or using an NFC reader connected to our Deck Topside. Then Android app can be used to configure a second RT 6-1000 which stays with you on the surface. For small boat operations, what could be simpler?

Alternatively, you can use our rugged and lightweight Shallow Water Deck Kit, comprising a Deck Topside with cabled Nano dunker.

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 it. When it’s time to recover it to the surface – and the valuable equipment it’s attached to – its screw-off release mechanism won’t let you down.

An optional attachment for the RT 6-1000 is a rope canister that allows items left on the seabed, for example; tools, cables and salvage, to be quickly and easily hauled up. It works by mooring one end of the rope to the item on the seabed and the other end to the RT 6-1000 via the attached canister of rope. As the transponder ascends to the surface, high strength rope is deployed from the canister. This line can then be used to pull up the item directly or retrieve heavier tag lines.

Why invest


  • Medium Frequency (19-34 kHz) 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


  • 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


  • 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


  • What’s in the box: RT 6-1000, shackles, release nuts (x10), manual on USB

  • Warranty: one year return to Sonardyne service centre

  • ITAR Controlled: No

  • UK Export License: Not required


Feature Type 8327
Depth Rating 1,000 m
Operating Frequency MF 20–34 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 Anodised aluminium alloy, plastic and super duplex stainless steel
Operating Temperature -5 to 40ºC
Storage Temperature -20 to 55ºC
Maximum Dimensions (Length x Diameter) 450 x 65 mm
Weight in Air/Water 2.0/0.5 kg
Standards CE Marked to EN-60945, EN-61010
Options Shallow Water Deck Kit (Deck Topside) 602-0175
Rope Canister (longer lengths available) 70 m (250 kg WLL), 120 m (250 kg WLL), 160 m (125 kg WLL)
Release Nut Part No. 830-0073 (note: 10 nuts supplied with each new RT 6-1000)

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Deploy, moor and recover equipment