Shearwater Tern TX Review

The Tern TX is now my backup computer to the Perdix, and I would dive either wherever and whenever I dive. Its compact size, clear display, and dependable air integration have earned my trust across pool training, local quarry work, and warm-water travel. Backup describes its place in my setup, not a limit on where I would use it.

By Tyler Allison · Updated October 2026
Shearwater Tern TX
Use
Travel, pool training, and local dives
Current role
Backup to my Perdix
Still in my kit
Yes

The Short Version

The Tern TX now serves as the backup computer to my Perdix. That is its role in my setup, not a limit on where I trust it: I would dive either computer wherever and whenever I dive. The Tern has never glitched, failed to sync, or run out of battery early in my use, and its smaller size does not make it feel like a lesser option.

Would I buy it again? Yes. I trust it as my backup to the Perdix and would be comfortable diving either one.

What Works

  • Compact, lightweight form that packs easily for travel
  • Bright, readable AMOLED display
  • Reliable air integration and Shearwater Cloud syncing
  • Rechargeable battery with quick charging through its USB-C puck

What Doesn't

  • Smaller screen than the Perdix
  • Fixed top and bottom rows limit screen customization

Why I Chose the Shearwater Tern TX

I wanted a lightweight, no-hassle computer for recreational dives, pool sessions, and warm-water travel without taking my primary tech rig with me. My Divemaster work and local fun dives rarely push limits, so I needed something air-integrated, durable, and simple. Staying within the Shearwater ecosystem meant shared transmitters and easy syncing to Shearwater Cloud. The Tern TX met that need without the size and weight of the Perdix.

What It Is Like to Dive

Readability
The display has stayed clear in silty quarry water and bright sunlight. Colors and contrast are excellent, although the screen is smaller than the Perdix.
Controls and Menus
The buttons are responsive, and I find navigation intuitive. The menu differs from the Perdix, but syncing and charging have been straightforward. Screen setup is slightly less flexible than on my Perdix.
Battery and Charging
A single charge has lasted multiple dives across several weekends. It charges quickly through the USB-C charging puck, and I have not had it run out of battery early.
Air Integration
The transmitter synced instantly and has never dropped its signal in my use. Pressure updates have been fast and stable, including during quarry dives and Divemaster work.
Comfort and Construction
It is lightweight and low-profile, easy to wear with or without gloves, and stays in place during pool work and quarry dives. The case feels protective and well-constructed, with no wear or scratches so far.

My Screen Configuration

Here is how I have the screen configured:

  • Top row: Gas type, battery level, current depth, and ascent rate (not customizable)
  • Second row: NDL and transmitter PSI
  • Third row: TTS, temperature, and GTR/SAC
  • Bottom row: Dive time (not customizable)
My Shearwater Tern TX screen layout with gas, NDL, PSI, and GTR

Setup is easy through the menu system. I wish I could move the dive time to a different location, but that is a small limitation in an otherwise logical and useful layout. The fixed top and bottom rows are the main restriction I notice.

Value and Support

The Tern TX is on the higher end of recreational-computer pricing, but its reliability, support, and performance justify the price for me. Shearwater’s support, firmware updates, and ecosystem consistency are strengths I value. It has worked well for my no-decompression diving and simple decompression use, rather than complex technical dives.

Who It Makes Sense For

It makes sense for recreational divers who want air integration in a compact form, traveling divers who want a lightweight rechargeable computer, and Perdix owners looking for a streamlined backup. I originally chose it for travel, pool training, and assisting, but its role has grown beyond that: it is now my backup to the Perdix, and I would use either throughout my diving.

When I Would Buy Something Else

If a large-format screen and maximum layout customization were priorities, I would choose the Perdix. The Tern TX has a smaller screen and fixed rows, but those differences do not stop me from trusting it throughout my own diving. That confidence is about how I use the two computers, not a claim that their feature sets are identical.