Marc T

Well sooooo many noise about teledyne but you rebreather guru did you ever thought about something better than the weird voting logic?

Even the oldest MK15 was certainly on a better ( less wrong way ? ) when his designer decided to choose the mean value of the sensors.
Voting logic would most realisticly be designed by "voting stupid" ( two wrong possibily stronger than one right ) so most of the time correct ( statistic) but from time to time completely wrong.
If you add poorly insulation from moisture or non moisture resistant matérial, what did you expect? from time to time an accident but is it really an accident?

Look back in the past and see who are ( or will be ) the historical winners?
-number one MK15 designer: great moisture protection, great position of the sensors, simple but great electronic, correct and safe ( a little big perhaps but you are aware ) user manual.
-number two Gordon Smith and the KISS concept ( either for the mechanical O2 add system and the simpliest/safest electronic concept )
-number three perhaps posseidon and his really logic system and no I will not speak about apoc , time will tell for both of them.

And what could be the greatest loosers ( on an historical wew point of course)?

-electrolung but just because it was too early
-AP ( errare humanum est, perseverare diabolicum est )
-VR technology the complexiest the better really ? Lost of common sense putting on the market a rebreather with faulty exhaust valve AND staying with this same faulty part because of CE mark...so a big commercial flop, turning on a poorly designed ersatz.
-meg who is so sure that he lead and that the over follow...

So what the future of the sport rebreather market?
Well thats depend on who is able to correctly use the existing sensors or who is able to design a fool ( rebreather maker ) proof sensor.

Just have a look at car or plane history, that will be the same for rebreathers

My guess? Look... no actual rebreather maker except posseidon had a serious look at the electronic system and want to ear about, what else?...mCCR

In both case a brain: electonical or human but a brain.

icestac

I am not sure I agree with this (unless I am interpretting your analogy incorrectly), but the Rebreather is just too small for anyone to make much money in it. Unlike the early days of cars and airplanes, most people will never have a need for a rebreather. So that market will never grow to a mass-market level. Who will fund the development of the next generation of rebreathers? The military? I have a sneaky feeling they may still be able to get Teledyne sensors if they wanted too (just a WAG -- I'd be interested to know if someone knows for sure on that).

Cheers,
Jeff

Chett.L

Hi Mark,

Although AI sensors had some reliability issues from batch-to-batch, the Prism Topaz, sensor placement and head design is reliable strongpoint of this unit too.


Best regards,

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Chett. L

lizardland

Really? Thanks to the averaging feature I had the controller bumping my PO2 way over 1.6.

Don't get me wrong, the only thing I'd swap my Mk15 for is a 15.5 but the averaging really isn't its greatest feature.

heyydude

I built both - original Analog and every version of our Digital since then.


I mean no disrespect to your opinion, but the Digitals are sooooo much better in sooooo many ways!

The thing is, when designing an op-amp circuit for any type of sensor, you have to choose a range which works well with your processor.

The old Analogs work fine, but if you have a completely dead sensor, they inserted a false value (I think it was 47% of the scale) - this can cause all kinds of problems, as Stuart hinted at.

There are better ways of handling this, but I'm not talking about them at the moment...



Kevin Juergensen
Juergensen Marine, Inc.

lizardland

Yep, that's what happened to me. I lost a cell (turned out cell wire had broken) so it makes an estimate, adds the two good cells to the estimate and averages it out over the three. Result, it thinks the loop PO2 is lower than the setpoint so starts pumping oxygen in. I can't remember if I got an alarm light on the primary but you definitely get a green "on setpoint" light so it isn't immediately obvious until you check the secondary. I probably had a few minutes on 1.6+ at 65m before I noticed. I was gutted as I was on a lovely WW1 cruiser with plenty of stuff that had only had a few divers on it.

heyydude

You'd get the "Alarm - O" lamps lit.



Happened to me many times...

It's amazing to me how we used to dive these things... How did we all manage to stay alive?



Kevin.

Nad

Someone already answered about this.

Both (or all if we consider also the apoc) use the "stupid" sensors finally!


Sorry? Maybe you don't know exactly how their first rebreather is born. Anyway I never considered myself an expert but I never had any problem with exhaust valve. But maybe I didn't understand what do you mean because on the two models they build what I think is for you the exhaust valve is different!

Did you ever try one of the units you suggest are loosers? (Meg, Ouroboros, Sentinel) or one of those you didn't even mention like the HH?


I don't say that Mk6 is a bad unit but it is build for recreational use. Electronic is ok but I have, in the worst case, to have the control of the unit. But maybe this is just me and few others.

Cars and Planes needed more than 100 years to become safer, and still they have some problems...

Don't forget that electronic is made by human and, more important, is used by humans!

Nad

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