To Nerd (or not)

[Cio]

I love it. I get there are reliability concerns but with that and not seeing it when in a BO, so should not be your primary. I find it to be excellent. I have about 100 hours on one and the battery life is getting short. still 6-10 hours but I assume service after next year will be required

The OEM mount is terrible and puts it in too far into your line of sight. I bought a low profile on from shape works and it is perfect now. It does take some tinkering to get it right so be prepared for that.

 

[broncobowsher]

NERD2 since 2019. I would do it again.
Too heavy? Myth.
It does take several tried to dial it in. The little bracket that comes with it is not the right shape. They know it, they expect you to bend it into what you need. You have to do this.
No haptic? Not an issue. I run a Petrel as the controller, the NERD is the backup/heads up. Once you take a good rebreather class you will learn that you need 2 ways of monitoring your PPO2. The standard Petrel on the wrist runs the show. The NERD watches over the show. You can get the Petrel3 with haptic now. So you will still have that.

You didn't mention which rebreather(s) you are looking at. That can have an influence as well.

Without a NERD you will typically still have some form of heads up, blinky lights. So it isn't a question of a heads up display or not, it is a question of what form of heads up you will have. The NERD has the benefit over blinky lights in that you have a full bailout computer. It is watching the PPO2 and calculates deco just like the Petrel you will likely be using anyway. If you loose the Petrel, you have exactly the same controls and calculated deco in the NERD. Or the other way around. Run blinky lights, backup computer, programmed on planned dive gasses. Close, but if you have been chasing some gas issues for the dive before calling it, your deco plans may not be matched to what you actually have been diving. The NERD actually knows what you have been diving. The NERD actually simplifies the backup computer plans.

Maybe unit specific, but I added transmitters and the NERD now tracks gas usage during the dive. Useful for post dive data analysis. Also ditches the gauges, so a little cleaner in terms of stuff hanging off your chest. The Petrel won't read the transmitters (maybe they changed this, but the last I knew the CANBUS controller Petrels were not compatible with transmitters the last time I checked)

I am also making the assumption that you are looking at normal rebreather configuration with a Petrel as a controller and the NERD as a monitor. There are other ways of doing stuff, you can do the NERD as the controller and a Petrel as a monitor. Or two NERDs (one controller, other monitor). Nerd controller and blinky light heads up. And the list of different ways is nearly endless. So what other configurations are you considering.

 

[LFMarm]

I have a NERD and a Petrel 3 on my rebreather. I really like the NERD for monitoring of pO2. For navigation and problem solving on the fly, the Petrel is easier. If I only had to have one (like I had for the first year on the rebreather), I would get the NERD

 

[Wibble]

Have a Nerd 2 on my Revo with 300 hours over 4 seasons. I cannot imagine what it would be like to dive without one as it's so useful to have all the information "just there". It's especially good when navigating with the Nerd compass: none of the arm-twisting associated with a wrist-mounted compass.

I have the Nerd on my right-hand eye, with the Petrel controller on my right arm. The Nerd does not obstruct your view and you can read both computers very easily (Revo's have five cells, so you can see them all). It is easy to change the Nerd's settings in front of your face.

There are some weaknesses. The charging clip is annoying sometimes, but you develop the techniques to get it to work. If there's problems it can be the USB cable to the charging clip. The battery needs regular charging but it will last over a weekend. Not a problem as it's charged by connecting the clip to the Nerd, the USB cable to the clip and a charging battery to the USB cable. It charges within 30 mins.

I've had the sensor replaced after it went a bit haywire; showing a 400m/1200ft dive. Shearwater were really good with this but as it was out of warranty (5 years old) there was a charge for that work. Was back with me within a week.

The one comment earlier about cannot see it in a silt-out. The Nerd works fine in very poor visibility, e.g. a couple of inches (5cm). It won't work if you're diving in a complete zero vis silt out where your primary torch cannot be seen even if it's next to your mask. Not even sure a flashy-light HUD would work in those conditions. However, swim away of that zero vis and voila! it can be seen again. IMHO this isn't a drawback for the Nerd's design.

If bailing out, the Nerd is a little difficult to see as the loop's out of your mouth. Unclipping the Nerd from the loop is fine so you can change the settings without any real issues (e.g. CC to OC, changing gases, GF-hi, etc.). When diving deep or overheads I'll use a stand-alone third computer (Perdix) to monitor the depth/deco as a backup to the main Petrel and the Nerd backup.

I highly recommend the Nerd.

 

[signix]

I would recommend to not try it unless you have the money to buy one.
I had a Nerd on my first CCR course (rental unit) and after a few dive on my unit with only a HUD I had to buy one to regain access to compass (which is more stable than on your arm) and deco information without checking my arm. I can use my hand (photography, light, line...) and still see my cells and deco informaiton. It can be silty and I can almost put it in my mask and still see if anything go wrong. I have used one with a rEvo and a Sidewinder and love it for both.

 

[mr_v]

I like the NERD.

Pros:
- Convenience.
- Shearwater product means Divetronix support, which is the #1 reason for buying anything Shearwater.

Cons:
- Charging - the charger is flimsy and if you lose your adapter, it is $85 for a little dinky thing.
- May interfere with your view - if you have a fixed mount, you're out of luck. An adjustable mount makes things easy.
- Your friends can't see your PPO2 as easily as they would with a HUD.
- Price.
- If you don't have a cap on it while on the surface, you may burn out the display. Get a Vortex scope cap.

Will I get another one? Perhaps. But if I buy a unit that has a HUD, I probably won't replace the HUD with a NERD.

 

[Marie13]

Thanks for all the pros and cons. I have a blinky Fathom HUD on my Kiss Spirit with a 4 pin connector. I specifically did that over a hard wired HUD as I wanted the option to later move to a Nerd if I wanted to. I have a couple of friends who are willing to loan me theirs for a dive if I want to try it out, so I can at least try it out before I drop the cash.

 

[Capt Jim Wyatt]

I have a NERD2 on my Choptima. I like it for the most part. I like not having a wire run down my arm for a wrist computer/controller.

I don't like my students having one because I cannot see the PPO2s, I can see their HUD though.

Adjusting to being able to see the NERD up close and the backup computer on my arm is an issue for me. But probably not for others until presbyopia sets in.

 

[Raphus]

I love the nerd on CCR. I would never dive without it anymore. It's very relaxing to have everything in front of you. Especially while task loaded.
The weight is no issue (I mean this thing weighs nothing compared to a loop, or bov)

 

[211ratsbud]

Youre going to be looking for a better mount. Battery is small so IMHO a few back to back cold water dives in cold environment can be problematic imho.

otherwise it is essentially all the data you need in one quick glance.

id buy one again.