quick Apeks Quantum (TUSA IQ-700, Dive Rite NiTek Duo) questions...

-Just a curiousity, why do I have to wait for 48 hours after a dive before I can switch to gage mode on the comp? Do all computers make you wait this long or is this one just extra conservative?

-In the "DIVE" mode as you flip through the screens, if you accidentaly change the mix2 settings, it will stay on a number for around 24 hours. Does this affect any readings or is it ok to have mix1 at 21% while mix2 states 21% as well. I don't dive nitrox so I don't know anything about this.

-Ascent readings: I'm always getting a warning. How slow am I supposed to ascend?? It seems like if I move even super slowly I'm going too fast for this thing. Is there any chance that there's something wrong with a sensor?

-I've been searching around with no luck for some info on how to build my own cable. Someone mentioned that there's info out there if I look for it, but I can't find squat. If anyone could send me a link that would be appreciated.

TinoD'Voe:

-Ascent readings: I'm always getting a warning. How slow am I supposed to ascend?? It seems like if I move even super slowly I'm going too fast for this thing. Is there any chance that there's something wrong with a sensor?

-I've been searching around with no luck for some info on how to build my own cable. Someone mentioned that there's info out there if I look for it, but I can't find squat. If anyone could send me a link that would be appreciated.

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I get ascent warnings immediately below the surface. Sometimes the depth reading fluctuates wildly when ascending through 10 fsw. It usually shows 0 fsw depth between 5 and 10 fsw. Sometimes depth fluctuates from 10 to 0 to 10 again. I don't know if that is standard behaviour or if it's the result of a bad sensor.

As for the cable, I bought an OEM unit. It works great, but it better work considering what I paid for it.

This has hapened to me as well - my conclusion is the depth sensor reading isn't sufficiently 'damped' in the computer programming for small sudden fluctuations as the previous generation Seiko Dive Rite NiTek 3 is. I just did a week of diving on Roatan, with my new TUSA IQ-700 on one wrist, and my veteran DR NiTek3 on the other wrist. Only 1 dive did the NiTek3 show an ascent warning (surge in the shallows at the end), but EVERY dive showed ascent alarm on the IQ-700. I switched wrists, putting the NiTek3 on my left wrist and IQ-700 on my right, after a night dive where right-handed me had my dive light in my right hand and my non-backlit NiTek3 on my right wrist (hmm - room for improvement in pre-dive planning . . .)and same result. They had it right, then looks like they monkeyed with it a bit too much, or forgot what they did right before. Heck, it would go off sometimes just from me pointing at someting I was showing the DM or my dive buddy wife - just from arm extension! It's great to have a sensitive instrument - as long as it's properly compensated.

Interestingly, the N2 loading algorithm in the IQ-700 checked out to be slightly more conservative than the NiTek3 when diving with both. I kept it a Safety Factor 0 through the trip. The IQ-700 always had a bit less no-deco time remaining on the display (whenever not 'maxed' at 200), added a 'dot' of N2 sooner than the NiTek3, took longer to 'lose' a 'dot' of N2 than the NiTek 3, and would generally show about 15 minutes more time required for desaturation at the end of each 3 tank air only dive day (no Nitrox at Reef House Resort).

On the IQ-700, I set both Mix1 and Mix2 to 21% O2, and set all 3 gases on the NiTek3 to 21% O2, so I could practice mix switching on both computers underwater. A few tries, and no problem with either one, it's just a different procedure for each computer. The 'Mix2" on the IQ-700 will 'blank' each night at midnight (if not in DIVE mode at midnight), while the Nitek3 only does that if a mix is set to > 21% O2. The only difference I can see on the IQ-700 if you use 21% O2 for both Mix1 and Mix2 is you will get the O2 warning alarm at 1.6 ATA ppO2 on Mix2 instead of 1.4 ATA ppO2 on Mix1, from the Manual. i certainly didn't push to either 1.4 or 1.6 ATA ppO2 while diving air - my deepest dive was 115 FSW this trip. So, I didn't personally test the ppO2 alarm settings (I really wouldn't want to, anyway).

If you're not Nitrox certified, I suggest you just leave Mix2 'blanked' until you get Nitrox certified and a better understanding of elevated ppO2 effects.