Which has a higher rate of failure a SPG or a transmitter?

[Garth]

The SPG spool o-rings due fail at some point which is the problem with regular gauges. That being said I don't own a transmitter though. My predator doesn't have that feature and it doesn't bother me that it doesn't.

 

[DaleC]

We are comparing apples to pizza. A hockey puck SPG is as simple as it gets, yet these things fail. An AI wireless computer is about as complex as they come offering up dozens of functions and configurable options. It's hardly a valid comparison.

The AI unit provides all the functionality one wants for recreational diving period. Depth, Dive time, Air Pressure, Ascent rates, Nitrogen loads, alarms indicating all sorts of stuff like low pressure and ascent rate violations, even how quickly you and your buddies are burning through gas, all on your wrist. Nothing else is necessary, a true one gauge solution. The SPG provides one thing and one thing only, tank pressure.

For whatever reason divers seem to want to use old technology. The rational seems rather flawed. In an age of computerized brakes on cars, and computer controlled everything many divers reject technology and I honestly can not explain it. Your life is literally dependent on technology on a daily basis yet many reject the very things the they depend on daily. I dive the Epic and have had unbelievably good luck with this computer. Granted I carry a backup. Everything electronic you subject to an underwater environment will break eventually. Your mileage may vary.

I'm really wondering why you need all that information for a recreational dive. Sometimes simpler is better.

I can but a top quality B&G SPG for $100 compared to an AI for $1000. That's a 10:1 cost ratio and I can do the same dives you do. So... if money is no object, and one wants to be "dazzled" by all the doo dad's, and if one is willing to call their dives because they can't get a signal then go for it, it's your call. I for one, am not impressed by how much money one can spend on extraneous equipment to do a simple task though.

As some others have said, they are a fun gadget but not a necessity. I often dive a J valve but sometimes use an SPG as a back up so I guess I'm just as guilty of embracing extraneous technology.

 

[endurodog]

I'm really wondering why you need all that information for a recreational dive. Sometimes simpler is better.

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With that line of thinking one could also say why dive, we don't need to. Of course that is a silly statement but all we do is because we enjoy it. I enjoy having that info at hand during the dive and I enjoy having it on my computer when I get home. When I down load I get all the data from the computer and a cool dive profile graphic. It also figures my SAC for me and more.

No one needs all the info we get from these computers, the old analog gauges gave a lot of satisfaction back in the day and even to many to this day, but it makes my diving more enjoyable to have that info. But it's a personal thing. To each his own.

 

[DiveNav]

.........but I'm curious how many AI transmitters will still be in use 40 years from now......

Not needed ..... 40 years from now divers will have bionic gills

 

[DiveNav]

......and there is no indicator to tell you when the battery is low......

actually .... Some dive computers DO have that indicator ...

 

[Hatul]

I'm really wondering why you need all that information for a recreational dive. Sometimes simpler is better.

I can but a top quality B&G SPG for $100 compared to an AI for $1000. That's a 10:1 cost ratio and I can do the same dives you do. So... if money is no object, and one wants to be "dazzled" by all the doo dad's, and if one is willing to call their dives because they can't get a signal then go for it, it's your call. I for one, am not impressed by how much money one can spend on extraneous equipment to do a simple task though.

As some others have said, they are a fun gadget but not a necessity. I often dive a J valve but sometimes use an SPG as a back up so I guess I'm just as guilty of embracing extraneous technology.

The information from AI does increase safety. For one thing it displays the tank pressure in one display along with depth and time making it less likely that you forget to view it. Also my Galileo Sol calculates the remaining time I have before I have to make a safe ascent without running out of air, making the miscalculation less likely. It also makes the calculation of rock-bottom easier--the minimum pressure to allow you and your buddy to make a safe ascent sharing air. On deep dives it's easy for the diver to miscalculate and is the cause of many accidents.

 

[Charlie99]

Based on observations while on many dive boat trips, divers have problems with AI computers much more often than they do with simple SPGs. I suspect that the vast majority of "failures" aren't really failures of the transmitters, but are instead simply a dead battery.

I typically run my non-AI dive computer until it complains about low battery, and I can still do a few more dives. OTOH, it seems like a lot of the AI computers and/or transmitters die with little or no warning.

If you use an AI computer, you should be extra careful about replacing batteries before they become a problem.

Charlie

 

[Colliam7]

In today's world of diving, which has a higher rate of failure a SPG or a transmitter? Our experience is the Old reliable SPG. . . . our repair dept. has more problems with the SPG's that we service than transmitters.

Interesting post. I would not have expected this experience, but it is certainly your experience, and I can't argue with it.

Personally, I have had one transmitter periodically fail to sync over a several year (6) period. I have had one transmitter flood (in salt water; ugh) and become unusable. Among the 12 SPGs I have on various regulators, I have had one SPG on a deco reg fail, and need to be replaced. I have one SPG that 'zeroes' to 300 PSI instead of 0 psi but is otherwise functional, and one 10 year old HP hose fail. So, in my experience, I would perceive the SPG as slightly more reliable, and definitely less expensive to replace.

I am curious - are the respective problem rates that you refer to absolute, or proportional? Obviously, if SPGs are used for 100% of dives by 90% of divers, compared to transmitters being used by 10% of divers (and possibly not for all of their dives), the absolute number of SPG problems would presumably be higher than for transmitters, even if SPGs and transmitters were, proportionally, equally reliable. Have your repair dept folks been able to quantify the denominators? Again, I am not disagreeing with your experience, merely curious. In the case of my failed SPG, I had to buy a new one to replace it, and checked when I did so to see if there was any warranty coverage (there wasn't). In the case of the 'non-zero' SPG, I asked our service tech if it could corrected (it couldn't). In the case of the hose, I had to buy a new one. So, if our shop service department was somehow tracking reliability, they would have 3 cases of some kind of SPG problem. In contrast, for the periodically non-syncing transmitter, I did nothing - the air-integration was a 'nice to have' feature, and I also dove with a SPG so I didn't do anything about it (other than check for similar SB experience). Yes, I ultimately replaced it, but only because it was stolen. Likewise, once the replacement transmitter flooded, corroded and became unusable, I gave up on air integration. So, our service department would not have been able to 'track' transmitter reliability. I wonder how many people actually go back to their LDS when their transmitter occasionally doesn't sync.

 

[beaverdivers]

Colliam7 - "I am curious - are the respective problem rates that you refer to absolute, or proportional?"

Good Question, let me ponder it and get back to you.

 

[MarkHerm]

I can't comment on transmitters except second-hand, but [...] the batteries go fairly quickly, and there is no indicator to tell you when the battery is low.

The battery of my transmitter lasts 150+ dives (most of them cold water) which is not that bad given that even fancy bottom timers nowadays will only last 10-20 dives before a new battery is needed (I am thinking of the Liquivision XEN). Besides, there is an indicator for low battery of the transmitter I am using. I'd be surprised if this was a feature unique to Suunto's hoseless AI computers but I don't have first hand experience with other brands.