Spg, AI, both

What do you dive

  • Spg

    Votes: 25 23.1%
  • AI

    Votes: 34 31.5%
  • Both

    Votes: 49 45.4%

  • Total voters
    108

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In essence, the two gauges will never agree. So, which is right? In reality, it probably doesn’t matter as we shouldn’t be completely draining our tanks. But, if you have two gauges giving somewhat different info, which do you trust?

Whichever one reads lower.
 
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Whichever one reads lower.
That safer, but personally I'd compare it to other SPGs or AIs. Perhaps asking a fellow diver to hook up their regs and compare (you'll loose a couple PSI of course). So far, most of my SPGs that have been off, have read low. However, nearly all of my other SPGs and AIs read close enough any minor differences are irrelevant.
 
SPG in spares box in car. I've had a few drop out issues but once connected to a short 9" hose zero issues. Would like to connect it straight to first stage but not reliable enough.
 
Well, no I did not dive with 2 SPGS before AI, any more than I would expect two SPGs or a SPG and a wrist computer on most rental gear today. In fact, when I started diving in 1965, I was cave diving with no SPG or computer because there was no such gear. We just had a single Voit Avalon regulator, a plastic backpack with a 72 cf steel tank with a J Valve, homemade full 1/4" wetsuit and homemade weights, USD mask, snorkel and fins. Did that mean I felt safe, or would not have had a serious problem if something happened to my regulator or air supply? Of course not. Today, we have the availability of all the safety and redundant dive equipment you can ask/pay for. Fortunately, I can afford to dive with as many computers as I like, or an AI and a SPG, or any combination of gear that I might choose. If my AI or SPG fails, I finish the dive. If both fail, I end the dive, and change out whatever failed during the SI. Since I don't dive as much as I would like, when I do get on the boat, I want to make the dives, and do whatever I can to insure that happens.
Could you give me advice on my next purchase? I am thinking of getting with the times and getting a dive computer. I had been thinking of getting one with AI but I figured it wasn't necessary and probably expensive. I currently dive a couple of times a day with just a depth guage and SPG and a Casio watch on my wrist.

I did briefly own a dive computer, maybe a decade ago which was a decade after I learned to dive. I have had the same SPG for the better part of two decades (made in Germany) and I have no reason to think it will fail anytime soon. I'm not that worried as I know my way around all my local dive sites but I am eager to travel again.

I had an Oceanic something or other and I hated it, so much so that I never bought anything Oceanic ever again. It beeped a lot and I had to press a button to see more data when I looked at it. I'm aware I could have probably changed some settings but it just seemed like a passing trend at the time. I was quite happy to upgrade back to a PADI dive table. I finished the course I was doing (PADI IDC) with a cheap Mares dive computer and it was OK, it's on my wife's wrist when we dive together now. She says she wants a better one too. So I am aware of how essential dive computers have become but I am not accustomed to using one.

There was also one time I used rental gear and an SPG sorta failed. It was imperial, which should have been fine for a gringo like me but I wasn't used to it. I was able to do the math until about halfway through that trip when it seemed to start showing me having significantly more pressure than I should have had which if not for my suspicious nature would have led to danger. No incident reported.

I have never used any transmitter and I'm thinking I should get a decent watch style computer for myself without AI and a fancy one with AI for my wife with a transmitter on my first stage for her to see because she's worried my SPG is nearing its end. Of course she'd want a transmitter on her tank too.

So I'm asking you because I like the tone of your reply to this thread. But anyone should by all means reply to me. Which computers should I consider for myself and which for her? I'm thinking Garmin Descent G1 for me, and a Shearwater of some sort my wife wants for herself. Anyone think those are good choices? They have to be rechargeable. I'll let my wife worry about transmitter batteries.
 
Could you give me advice on my next purchase? I am thinking of getting with the times and getting a dive computer. I had been thinking of getting one with AI but I figured it wasn't necessary and probably expensive. I currently dive a couple of times a day with just a depth guage and SPG and a Casio watch on my wrist.

I did briefly own a dive computer, maybe a decade ago which was a decade after I learned to dive. I have had the same SPG for the better part of two decades (made in Germany) and I have no reason to think it will fail anytime soon. I'm not that worried as I know my way around all my local dive sites but I am eager to travel again.

I had an Oceanic something or other and I hated it, so much so that I never bought anything Oceanic ever again. It beeped a lot and I had to press a button to see more data when I looked at it. I'm aware I could have probably changed some settings but it just seemed like a passing trend at the time. I was quite happy to upgrade back to a PADI dive table. I finished the course I was doing (PADI IDC) with a cheap Mares dive computer and it was OK, it's on my wife's wrist when we dive together now. She says she wants a better one too. So I am aware of how essential dive computers have become but I am not accustomed to using one.

There was also one time I used rental gear and an SPG sorta failed. It was imperial, which should have been fine for a gringo like me but I wasn't used to it. I was able to do the math until about halfway through that trip when it seemed to start showing me having significantly more pressure than I should have had which if not for my suspicious nature would have led to danger. No incident reported.

I have never used any transmitter and I'm thinking I should get a decent watch style computer for myself without AI and a fancy one with AI for my wife with a transmitter on my first stage for her to see because she's worried my SPG is nearing its end. Of course she'd want a transmitter on her tank too.

So I'm asking you because I like the tone of your reply to this thread. But anyone should by all means reply to me. Which computers should I consider for myself and which for her? I'm thinking Garmin Descent G1 for me, and a Shearwater of some sort my wife wants for herself. Anyone think those are good choices? They have to be rechargeable. I'll let my wife worry about transmitter batteries.

if you want a transmitter on your tank that is being read by your wife’s computer, then the range necessary for that to work pretty much dictates that you have a Garmin transmitter and your wife has a Garmin computer.

The transmitter used by Shearwater, Oceanic, Aqualung, Hollis, and some others (I think) does not have the range to be read by another diver’s computer. Not anywhere near what you’d call reliably, anyway.
 
if you want a transmitter on your tank that is being read by your wife’s computer, then the range necessary for that to work pretty much dictates that you have a Garmin transmitter and your wife has a Garmin computer.

The transmitter used by Shearwater, Oceanic, Aqualung, Hollis, and some others (I think) does not have the range to be read by another diver’s computer. Not anywhere near what you’d call reliably, anyway.
but she could get within range and it would kick on with a reliable reading if she had to? I don't mind if my wife has to work harder for me to be more comfortable.
 
but she could get within range and it would kick on with a reliable reading if she had to? I don't mind if my wife has to work harder for me to be more comfortable.

If you have a Shearwater-compatible transmitter and she has a Shearwater AI-capable computer, and she gets her computer within arms length of you transmitter for 5 seconds or so, it should show her your tank pressure until she moves back out of range.

It would probably be easier to just mount a large dial SPG somewhere on you where she could see it.

But, if you really want the AI, then check out the Shearwater Tern TX that was announced today. I think it’s exactly what you want. And you might like a Tern for yourself. Or even a Tern TX.…
 
If you have a Shearwater-compatible transmitter and she has a Shearwater AI-capable computer, and she gets her computer within arms length of you transmitter for 5 seconds or so, it should show her your tank pressure until she moves back out of range.

It would probably be easier to just mount a large dial SPG somewhere on you where she could see it.

But, if you really want the AI, then check out the Shearwater Tern TX that was announced today. I think it’s exactly what you want. And you might like a Tern for yourself. Or even a Tern TX.…
That's useful info, and I'm looking mainly at Garmin and Shearwater. I think I'm leaning Garmin. The transmitter thing isn't make or break, I will use an SPG either way. I just prefer it. Currently, the plan if my SPG fails is I just keep going until I deplete my tank and then we share hers to the surface. She's this tiny, mean, gorgeous little Filipina and always has more air than I do.

I have my SPG attached to my reg for a little over 20 years but I did switch the hose a few years ago which required removing the rubber boot. I put a fairly long braided hose on it and a shackle snap bolt that hooks to a d-ring on my harness and the SPG itself which still hangs another 30cm beyong that just goes in my pocket. My depth guage is an even older wrist mounted thing that I no longer trust and not only because the wrist strap is broken. It could be more than 30 years old.

My SPG is fine, it's the Mares one that actually came with my reg but it says "Made in Germany" right on the face and I'm planning to use it for another 20 years. If it doesn't last, I'll get another metric analog SPG of the highest quality I can find. I have a solid dive buddy anyway.

Anyway, I'll study up on the Garmin AI thing, sounds like the way to go.
 
That's my sidemount rig and I'm pretty happy with it. I have no concerns with the reliability of the transmitters, but a button SPG is really helpful when setting up and checking if it holds the pressure.

1699938671737.png
 
CCR, Sidemount and Recreational AI only. Twinset both. Stage, Deco, Bailout SPG only.
 
https://www.shearwater.com/products/teric/

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