How accurate are Suunto wireless-air transmitters?

[esguerra1]

Thinking of purchasing the new Suunto Vyper Air but I've never used a wireless transmitter underwater to gauge air pressure/consumption. How accurate are these?

Have any of you owners ever experienced problems with pairing or inaccurate/unable to read situations? Just want to get peoples' impressions of reliability and ease of use.

Aloha,

 

[Colliam7]

Thinking of purchasing the new Suunto Vyper Air but I've never used a wireless transmitter underwater to gauge air pressure/consumption. How accurate are these?

Interesting question. To determine 'accuracy' what would be the reference standard? In comparison to my SPG, I have always found the transmitter / computer to be consistent with my SPG.

Have any of you owners ever experienced problems with pairing or inaccurate/unable to read situations?

Unable to read situations - yes. I have infrequent problems with pairing, but they do occur. Usually, part of the problem in my case is user error - it is helpful to pressurize your tank, with the computer and transmitter in reasonably close proximity, and verify that the 'system' is working before getting in the water. I have also noticed that pressure readings become less reliable at lower tank pressures. If I get down below 600 psi, I am more likely to get a 'Fail' message displayed on my computer instead of a pressure.
There are SB several threads in which the reliability of wireless systems is debated. Some divers go entirely wireless in order to eliminate a hose, others like to have the redundancy of a SPG. I use my transmitter for convenience - easier to turn my wrist to view pressure (and depth) than unclip the SPG - and keep my SPG attached for back-up. That's a personal preference and you will probably get differeing opinions.

 

[tstormdiver]

I just got a HelO2 with a transmitter (the transmitter for my recreational outfit). It does seem to run accurate with the SPG as mentioned above. The biggest problems I have heard with pairing the transmitter & computer, is if there are several computers that run on the same code that are too close to each other. The first computer activated will pair with all the like coded transmitters, rendering the others pretty much useless.

 

[RJP]

The first computer activated will pair with all the like coded transmitters, rendering the others pretty much useless.

Considering - at least with Suunto - that there are 99 potential pairing codes, the likelihood that your computer will pair with my transmitter is pretty low. In fact. in addition to having the same code selected, we'd also need to be pairing at the same time AND have both of our transmitters and computers within about a foot of each other. Possible theoretically? Sure. Likely to ever happen in practicality? Nope.

 

[RJP]

Have any of you owners ever experienced problems with pairing or inaccurate/unable to read situations? Just want to get peoples' impressions of reliability and ease of use.

Vytec DS here.

The only 2-3 times I've ever had problems have been of the "user error" type - failure to sync computer and transmitter prior to entering water, etc.

Keep in mind that when you switch over tanks between dives, or go a long time between setting your gear up and getting in the water, that you'll lose the signal between the two. Re-pairing simply requires pressurizing the tank next to the computer, so not an issue in practicality. But on occasion I've jumped in the water without the two paired. Not a problem as I too dive with a backup SPG.

300 dives on my Vytec DS and I've never "lost the signal" during a dive. Never heard of anyone who has either. Suppose it could happen if the battery conks out or something.

Accuracy? Seems to match my SPG. But what you ought to keep in mind is the idea of "accuracy vs precision" as related to measuring instruments and observations.

A digital computer will report PSI to four digits (ei 3442 PSI) however the part of the instrument that actually reads the pressure is nowhere near that precise. A rule of thumb I was taught in cave diving is to assume that any computer, SPG, etc is precise only down to 500psi increments. ie 3442=3000psi, 3001=3000psi, 1200=1000psi, 750=500psi, and with 500psi showing every breath after that is merely a pleasant surprise.

 

[Rhone Man]

My experiences are very similar to RJP's. I use a D9 with wireless, any my 2 psi for what they are worth are:

- accuracy looks good when compared with analogue SPG
- never had a problem pairing up, but after a while (a few mins) the transmitter goes into sleep mode if you don't start diving, and you have shut off your air, purge it, and turn tank on again to kickstart it (nb, the instructions say as soon as you breathe it will detect a drop in tank pressure and start transmitting again, but that is not my experience - it won't go to sleep if you are breathing, but breathing alone is not enought to "cold start" it).
- never yet lost a signal whilst diving

 

[tstormdiver]

Considering - at least with Suunto - that there are 99 potential pairing codes, the likelihood that your computer will pair with my transmitter is pretty low. In fact. in addition to having the same code selected, we'd also need to be pairing at the same time AND have both of our transmitters and computers within about a foot of each other. Possible theoretically? Sure. Likely to ever happen in practicality? Nope.

It has happened several times to divers from our LDS while on shop sponsored boat trips. Maybe luck of the draw, or getting batches of computers that are coded the same. I don't know. Just know it has happened. Mostly with the Vyper Air & D9 computers. As for the HelO2 computers, there are only 7 of us there, who have those, so not so much of an issue.

 

[RJP]

Maybe luck of the draw, or getting batches of computers that are coded the same.

The codes for Suunto computers are "rolling codes" in that the transmitter assigns a code to the computer on the fly. The codes are are not "factory set."

I guess it could happen if two divers, in ultra-close proximity, are performing some sort of exquisitely timed synchronized synchronization. But that sounds more like "user error" than any problem or shortcoming with the Suunto.

 

[Dave1981]

I've seen it happen where a friend lost signal mid dive and never had a backup SPG, he did know the batteries were running low though so not entirely unexpected

 

[Ocean County Diver]

I've had the same experiences as RJP. Lost connectivity between dives many times due to the inactivity but all you need to do is repair them as RJP stated. Never lost a signal during a dive that I can recall.

Personally, I would never use this as my sole source of pressure monitoring. I always have a SPG with me, so the wireless is just there to help me see my SAC rates when I download my dives to send to DAN for PDE.