Affordable Dive Computers

[Belzelbub]

I am considering the Aqua Lung i470tc, because the design is similar, and according to my local dive shop, Aqua Lung uses algorithms that are close to those used by Oceanic. I also like that this model is a little more state-of-the-art with Bluetooth capability. Though I'm not currently interested in air integration, I like that this model has that capability, should I change my mind and decide to splurge on a transmitter.

Another option might be the Oceanic Geo. It will run the same DSAT algorithm that you are used to. The Geo 4.0 or the Geo Air are good choices. The Geo Air has air integration capability and is pretty reasonably priced.

And yet, after reading Brett Hatch's comments about the Shearwater Peregrine, I did a bit of research and am intrigued. Though I dislike the idea of a bulky square computer on my wrist, the full-color screen on this one does look attractive. I also like the USB re-charging capability and that it has a vibrating alert option. But I wonder if the algorithm is different enough from DSAT to be a problem.

@scubadada regularly dives with a Shearwater Teric and an Oceanic VT3 (IIRC). So one with Buhlmann, like the Peregrine, and one with DSAT. From what he's said in other threads, the Peregrine would be able to be set liberal enough to do a reasonable job of matching the DSAT algorithm.

The other computer you mentioned doesn't run DSAT either. It runs PZ+ which is based on Buhlmann, but not exact. It would be more conservative than the DSAT you are currently using.

 

[Billg68bg]

I have a TUSA TC 1. Christmas present. Seems like a nice dive watch/computer. Only used it on one trip. Three dives + an accidental pool dive when I forgot to change the default settings and dive in to a pool. Does time/date, time down, max and avg depth, stops, etc. graphs the dive and holds up to 999 dives. Anyone familiar with this computer? Thoughts?

 

[inquis]

the Teric's algorithm can be similarly configured to be close to DSAT?

Yes, it can. The Teric is a great piece of kit.

 

[scubadada]

Hi @Alex_Garland

Your OCS runs both DSAT and PZ+, you chose to run DSAT. DSAT is a liberal decompression algorithm. PZ+ would be considered moderate or middle of the road.

The Aqua Lung i470tc runs just PZ+. It would control all of your dives due to its more conservative decompression algorithm. Looks like it goes for about $550

The Peregrine and Teric run Buhlmann ZH-L16C with gradient factors. Both have 3 presets and a custom setting, if you know what you are doing. The preset of 45/95 matches DSAT reasonably well, a little more conservative on 1st dive, especially deeper, a little more liberal on repetitive dives, especially shallower. The 95 setting is the GF high and controls the NDL on no stop dives. The 45 is the GF low and controls the 1st deco stop depth in decompression, does not apply to no stop dives. As per @Belzelbub I have been diving an Oceanic VT3 running DSAT since 2010, an Oceanic computer running DSAT since 2002. I have been diving a Buhlmann computer since 2015, a Teric since 2019. I love my Teric, it is a great computer for me, see below. The Peregrine goes for $530, the Teric for $1170, without transmitter. The Teric and the Geo Air use the same transmitter. I run my VT3 and Teric off one transmitter.

The Geo 4 and Geo Air run DSAT and PZ+. My family still dives a Geo 2, a fine computer, I would imagine the Geo 4 is too. The Geo 4 goes for $440, The Geo Air goes for $549 without transmitter. Oceanic offers a Geo Air bundle with transmitter for $800, $150 savings on the transmitter.

You have several fine choices for your second computer, best of luck.

Hi Alex, sorry, forgot to tell you, turn off your audible alarms, p 21 of your manual

 

[boulderjohn]

I have been diving an WHATEVER running WHATEVER since 2010,

When contemplating the cost of a computer, divide the cost by the number of years you expect to use it. If scubadada had paid $500 for that computer in 2010, his annual cost for it would be under $40, and I suspect he would think it was worth it.

I bought my first computer a quarter century ago. After about 16 years I sold it to a new diver friend because he needed one, and I had stopped using it because I did not like the Suunto algorithm. A few years later he decided he did not like the algorithm, either, and he sold it to someone else. It might still be in use today. I don't know.

 

[scubadada]

...I suspect he would think it was worth it.

I got the VT3 and a transmitter for about that price as the computer was soon to be replaced by the new VT4. I got a good one, 12 1/2 years, 1818 dives and 1915 hours

 

[Hoag]

You mean you just continued to dive with a fresh new dive computer that didn't account for your residual nitrogen from prior dives as if it were your first dive in the trip?

Go back and read post 11 in this thread where I explain it in more detail. I didn't think I needed to repeat the entire story so I didn't.

 

[Eric Sedletzky]

2006

Info - History of PADI's Enriched Air Nitrox course

I was looking for something else in the old PADI Training Bulletins and found this information: 1996 EANx first offered. Prerequisites were AOW or OW plus 10 logged dives. 2 OW dives were required. 2000 Prerequisites of AOW/10 dives dropped. 2004 DISCOVER EANx offered; 32% maximum, no...

scubaboard.com

Too many shops complained that they wanted to sell the course but couldn’t complete the dives because they didn’t pump nitrox. My shop was one if them. When I took PADI nitrox it was through the shop but the instructor was also doing PP fills in his garage then topping up at the shop. Not sure if that was legal or legit but we had nitrox. He moved away and that ended.

 

[boulderjohn]

Too many shops complained that they wanted to sell the course but couldn’t complete the dives because they didn’t pump nitrox. My shop was one if them. When I took PADI nitrox it was through the shop but the instructor was also doing PP fills in his garage then topping up at the shop. Not sure if that was legal or legit but we had nitrox. He moved away and that ended.

I worked for two shops. The first one did not have nitrox. Period. There is no need for it within Colorado.

The second one gets their nitrox as you described it. Someone who dives mixed gases elsewhere periodically comes in and puts the appropriate amount of oxygen in their nitrox tanks, after which they top them off with air. The air from their compressor meets standards for oxygen service. Nothing illegal about it.

That someone is me. I also service their nitrox tanks.

 

[Belzelbub]

When contemplating the cost of a computer, divide the cost by the number of years you expect to use it. If scubadada had paid $500 for that computer in 2010, his annual cost for it would be under $40, and I suspect he would think it was worth it.

Or even better if you divide it by dive...

I got the VT3 and a transmitter for about that price as the computer was soon to be replaced by the new VT4. I got a good one, 12 1/2 years, 1818 dives and 1915 hours

~$500 over 1818 dives is just a bit over a $0.27 / dive. Or, hourly, just over $0.26 / hour.

So yeah, probably worth it.