The Hammerhead

Some of us have been unlucky enough to have electronics issues with the current head ( I have a flaky connection to cell 1 for example). I also would like more independence on the handsets and a HUD (Heads Up Display) for when I'm not looking at the handsets.

So it was welcome to see that there are alternative electronics units out there. I was fortunate to be in the first order batch so

see http://www.electricfilm.com/hammerhead.html for full details. but here are the main bits

Hammerhead Unofficial User's Guide
Official Status Report
Mounting the Wrist units
Quick shots of my unit
Hammerhead direct

So far utterly stunned by how much is in this package, took me a while (with Kevin's help) to suss out the menu's, so to save everyone time I've stared on the Unofficial Users guide to the Hammerhead

Its a Word .doc at present but when its a bit better and more stable I will PDF it, Please download and use it, but tell me anything that's wrong or missing

Hammerhead Unofficial User's Guide

top...

Official Status Report

OK so the unit is still in development and improving fast. Kevin is swamped with folks e-mailing and calling him so Kevin and I have agreed for him to post a weekly status report which I will host here.

Report 17/6/03

1) We have 100 Heads now fully cut, awaiting the Engraving on the
top. Those should be done by next week, and ready for assembly.

2) I spoke with Jim (the software guy) this AM about our progress,
and he believes he'll have something worked out for me in the
Proportional Control area at the end of the week. We'll then test it
out on the bench, and if it works well, will distribute it to
selected divers for in-water testing and verification.

3) Meanwhile, we have more and more reports of successful dives on
the Hammerhead, with more VR-3 Traces to put up on the web site -
which I'll try to do in the next few days.

Steve Cowley now has over 45 dives on the Hammerhead. Mike Dyson has
about as many as Steve, at up to 71 Meters (234 fsw) - Mark Nix has a
few too, but I'm not exactly sure how many total. Lots of other guys
have sent me e-mails about successful dives with the unit, but these
three seem to have the most.


4) Hardware Updates: We have issued the P.O. for engineering
development of the new boards, which will include all the hardware
goodies I mentioned in my last "Mole" report. Once again, these
things take time, and those of you who are waiting anxiously for
these updates please be patient while we build them, test them, and
make sure they work just like you want them to. These updates are
going to make the Hammerhead the most advanced CCR
Controller/Decompression Computer in the world, so your wait will
prove very worthwhile.

5) Mechanical Updates: We're also working with a new design firm to
make changes to the Wrist Unit which will make fabrication/repair
easier and cheaper. Right now, the existing Wrist Unit is doing
really well out there, with only one guy (Tom Mount) so far busting
one up (the Back, which as most of you know we have replaced with new
Lexan). There is one change to the Head that is coming up which is
rather inconsequential to the end-user, so there really isn't any
need for me to bring it up.

6) We slowed down shipments of the new HH's to end-users so that we
could a) Add the new Backs and Strap Retainers, and b) to add the
latest Software (when it is done). If you are waiting for your
Hammerhead, this is most likely the reason (see the recent post from
Rob Drury). 3rd Run Orders are still in the building phase, and will
have all the new software already installed.

7) Speaking of software: Phi Le has agreed to pick 5 to 10 of the
Gradient Factors proposed by Joe Radomsky and give his reasons why he
feels that they should correspond to the Conservatism Factors of 1-5
(or 1-10 as the case may be) - we're going to open that up to public
debate, which is a huge mistake I'm sure... ; -)

We'll then integrate those numbers into the HH as the Conservatism
Factors (which will then be published for all to see) which will be
available as the "Standard" Conservatism Settings. Note: There will
*also* be an "Advanced" Gradient Factor Menu which you can elect to
use instead of the "Standard" one where you will be prompted to enter
your Hi/Lo Gradient Factor - so those of you who keep telling me that
you "know this stuff inside and out" can enter your own combo's.

Once again, my reaction to various opinions is to simply give you the
choice as an option, rather than dictating what you have to use.
We'll have limits on it, so people can't bend themselves (unless they
just want to blow off stops), but beyond that, you'll be free to let
your imagination run wild.

8) Everyone who I've talked to who knows Deco says that if we do the
above, then we don't need Pyle Stops, so I guess Ritchie is being
blown out of the water, to use an apropos metaphor... ; -)

Problems: Here are the problems we've had in the last week or two:

a) One diver reported that they got water in the Fischer Connector
after a dive. After discussing it with them (over e-mail), and then
with another diver, it was determined that the water might be coming
from the Fischer Connector Sleeve AFTER the dive, when the unit is
disconnected. This does NOT affect the dive at all. The diver who
reported this condition is going to get back in the water next week
to give it another go, and to observe his unit closely to verify that
everything functions properly.

b) We had one more unit drain it's battery too fast because of the
Dip Switch being set to the "on" position. I sent Mole some photo's
of the proper and improper position of this, which I believe he has
posted to his website. This problem will vanish in the next
software/hardware update and will no longer be an issue. However, if
you notice that your screen dims, or your unit "restarts" (you see
the "Juergensen Marine" startup screen over and over) then you have
dead batteries.

c) Batteries: I've had a few guys tell me that they are having
problems finding batteries. Here in the States, there is a source
for these batteries that is cheap. Here is the link to the exact
battery we use in the Secondary (which will work just fine in the
Primary, too, by the way) - it is like $9 each - way cheaper than
I've heard you guys getting charged by the local computer store:
http://www.zbattery.com/zbattery/ls14250.html

Again, when we have the new Hardware done, you'll be able to use a
1.5v AA alkaline cell if you need to.

d) Calibration: I've fielded a bunch of calls from guys about
issues that turn out to be Calibration related. I had thought that
over the last 8 months I had explained this properly, but I need to
do it again. Below is the right way to calibrate the sensors on a
Hammerhead:

* Remember you have a very powerful tool in the HH with the "MV
Display" menu (available in the OPT menu). I suggest you use this to
your advantage in a number of ways - the first being verification of
100% O2 concentration in your loop (or as close as you can get to
100%). Here's how you do this:

* Take the Head off your rig.
* Put your R-22 Sensors in a baggie, along with your O2
Analyzer (so you can independently verify your O2 concentration)
* Plug your Sensors into the Banana Block of the Hammerhead
* Turn on the Primary and Secondary Display
* Select "MV Display" from the OPT Menu of the Secondary.
* Add Oxygen to the baggie until your O2 Analyzer (visible
throught he plastic) reads 100% (or 99.8, etc, you know what I mean).
* Read the mV output from the 3 Sensors as displayed by the Secondary.

THAT number is what your sensors should be expected to output in a
100% O2 environment - meaning, if you put the sensors back in the
Head, put the Head back on the rig, and then drive out to the ocean
to go diving, and do a loop flush on the boat of O2 for calibration
purposes, those sensors should read the same number on the Wrist Unit
(either Primary or Secondary) as they did in the baggie. If they are
lower, then you have NOT flushed your loop properly.

* Remember, our electronics will REJECT any sensor which does
not output a minimum of 40 mV in 100% Oxygen. If your sensor will
not output that minimum voltage, then it is likely bad.

* Once you have checked this mV output on the bench, then go
ahead and Calibrate BOTH the Primary and Secondary Displays. These
units hold calibration very well, so you don't have to keep
re-calibrating them every day, provided the mV output in 100% O2
remains relatively the same.


Shipping Delays: Once again, I apologize for delays in getting units
out to those of you who are waiting. The 1st and 2nd Runs are just
about all delivered, and the 3rd Runs are in production, as I noted
above. We're going to have another burst of deliveries like we did a
couple weeks ago when this new software is done, and we will be
making an update facility ready for you guys in the UK that is
friendly and quick.


That should just about do it for this week's report. Things are
moving along here, and I want to get units in everyone's hands
quickly. That will happen very soon, then we will actually have
stocked inventory of units which we can ship upon order. Future
updates will happen on a somewhat timely basis

I need to get this off to Mole so he can go to sleep.

As always, everyone knows my number, if there are any specific
questions you'd like answers to, please don't hesitate to call.

Take care,

Kevin Juergensen
Juergensen Marine.
 

DIP SWITCH UPDATE

Report 2/6/03

On Friday, I met with our Software/Hardware engineers and we worked
out some issues to be resolved in the next version of the Hardware.

We have to build more boards because the initial run was to cover 52
sets of Hammerheads, and we now have a total of 75 sets either
delivered, being shipped, being prepared for shipment, or on order.

We also have dozens of outstanding orders for CCR Controls (Mark
15/15.5 and others) which we need to fill.

Since there were 2 "greenwire" fixes that had to be made on the
current revision of electronics, we had to do a re-design of the
board anyway, so I've elected to go the whole nine yards on the next
rev. This will include:

HARDWARE

a) New Power Supply: You'll be able to use a AA battery if you
want, or the current 1/2 AA Lithium sets.

b) Battery Display: Low Battery Warning will be included in the set.

c) Backlight Brightness Control: You will be able to adjust the
brightness of the backlight.

d) LED Brightness Control: You will be able to adjust the
brightness of the LED on the HUD or Wrist Units.

e) LED Activation Control: You will also be able to select which
LED's where you want to activate, and when you want them activated
(the new "DAC" Dynamic Alarm Control).

f) IRDA: Yup. Infrared I/O. It will take a while to build the
software for it and make sure it works, but the hardware will be in
there ahead of time.

g) Audio Alarm: When I was over at the factory, they had a new
Heart Monitor they had built which had this small piezo-electric
beeper on it that was louder than hell, and tiny. So I told them I
want that on our board too. You'll be able to enable/disable it if
you want.

h) Flash Memory: We'll have it available for the

i) Hide Diagnostics

j) Dip Switches

316 microamps during sleep

etc...

 

Report 26/5/03

Today is Memorial Day, so it's a national holiday, and no one is working - not even me - I worked Saturday and Sunday instead, and am playing with the kids today.

There isn't much to report this week - everything that we talked about last week is still ongoing, except that I'll be picking up the new Lexan Backs and Stainless Steel Strap Retainers on Wednesday.

Another 5 Hammerheads came in at the end of the week, so we should have more happy people out there pretty soon.

We're going to be taking delivery of the new Heads 10 to 20 at a time (we've ordered 100), and are going to hopefully have all of them done by the end of July, so we should be well taken care of for any additional orders that will come this summer.

Since there isn't much new to report in the way of stuff happening (things don't happen in one week in this business it seems) - I thought that maybe I'd write a piece that is best described as "Random Thoughts".

As all of you know, we are designing a new algorithm for the Hammerhead - the reason we are doing so is because we have had reputable folks such as Mike Dyson, Steve Cowley, Mark Nix, Dave Thompson, Bob Howell, and even our old pal the Mole giving us feedback about Set-Point management for the last few months.

The debate - and make no mistake about it, it IS a debate - centers around how critical maintaining Set-Point is in a CCR. Now, at first blush, it may seem like a no-brainer, obviously a CCR should maintain Set-Point perfectly - that is, no matter what you are doing, ascending, descending, working hard, relaxing while studying fish, the CCR should keep Set-Point exactly where you set it.

But the real world does not work like that.

And let me get one thing out of the way right here - I have had conversations with almost everyone who has purchased or ordered a Hammerhead, as well as notable CCR divers such as Richard Pyle, Tom
Mount, John McKenney - and with the exception of about 3 divers, everyone claims that their units (Inspirations, Cis Lunars, Mark 15's, etc.) exhibit no better accuracy than a tenth of a ppO2 (.1) during normal dive operations, meaning throughout a complete dive, ascending, descending, zig-zag patterns, diluent flushes, etc. I myself have been diving rebreathers longer than many of you out there, and have never seen anything maintain .01 (hundredth of a ATM). I do not believe for a minute that all the Inspirations out there maintain ppO2 that closely.

That said - I'm not making an argument for sloppy ppO2 maintenance, but merely pointing out that many arguments I've seen lately on the Internet are rather "academic" in that they purport that swings of a tenth of a ATM affect diving operations - which they in fact do not. I will make my point about this here, then move on to the different considerations we're balancing during the further development of the Hammerhead software.

Let me explain: For all intents and purposes, the only reason to want Set-Point Maintenance as good as, or better than a tenth of a ATM is for decompression considerations, for clearly you only need .21 regularly to survive, and you would probably prefer not to breathe anything over 1.8 for very long. So - If you are diving a decompression dive, and your tables (notice I did not say computer, for in the case of the Hammerhead and I believe the VR-3, the actual ppO2 output from the Sensors is taken into consideration) is basing your decompression stops and TRT on a Set-Point of 1.2, but your loop ppO2 is averaging 1.1 throughout your dive, you will not under any normal
decompression table, get bent due to that tenth of a ppO2 deficit - if you DO, then you were most likely asymptomatic for DCS anyway, even at 1.2.

Read that again: A tenth of a ppO2 is not enough to make a tinkers-damn in Hell when it comes to decompression. If you are cruising the edge of DCS that closely, you are more than likely getting bent on every dive anyway, and just not feeling it. 5 more minutes in the water is not going to necessarily kill you (as long as you're not breathing that same water) - so cutting your deco down to the absolute minimum will one day make you very unhappy - trust me. I have several friends with hip replacements, shoulder replacements, and fused vertebrae to attest to lifetimes of treating deco like it was some kind of nuisance. This is why everyone gives the end-user degrees of conservatism in their dive programs - us included. Deco is an inexact science at best.

Way back when, when there were only a handful of us diving CCR's outside the military, we decided (since we all knew each other) that 1.2 seemed a good place to dive our Mark 15.5's (and in the case of Rich Pyle, 1.3 on his Mark 4 and 5's). The US Navy was still diving .7 in the Mark 15's and 16's.

We knew then that according to the Navy even though it was rare, they had had guys tox out at 1.8 in the chamber, and it didn't seem to matter what condition the diver was in, or what the specific condition was - it happened almost randomly. I believe it still does. Some divers, I'll mention Rich Pyle here again, have done dives at 3 to 4
ATM of O2 and not known it for minutes before checking their displays. Once again, Otox is another inexact science, and no one can be sure when or who it will strike. So when it came to Maximum O2 Exposure, it seemed that 1.2 ATM was high enough to give some deco benefits (over .7 for sure), yet far away enough from the "magic" number of 1.6 (which we decided was far enough away from tox to be the maximum safe distance) that we could handle some spikes during the dive.

The Mark 15, 15.5 and 16 maintain Set-Point to around 10% +/- In all the literally thousands of decompression dives done by all the Mark 15 series divers I know, none of them have ever been bent when following tables - I do know a couple who have been bent when they blew off significant amounts of shallow stops, but none from following relatively conservative tables.

This is my long way of saying that I think that stressing the accuracy of Set-Point maintenance to less than a tenth of an ATM is a bit like picking fly poop out of pepper. It really, really doesn't matter worth a hill of beans, folks - really. You can argue all you want about it, you can make a big deal out of it, and draw graphs and charts showing
how it "should" affect things, but the bottom line is that in real live down and dirty diving, the only thing that is important is that you don't drop below .2, and you don't climb above 1.8.

HOWEVER: Now that I've belittled the subject, let me tell you how we're approaching the improvement in the Hammerhead algorithm. Pointing out the relative insignificance of maintaining a loop ppO2 better than .1 does not mean that it is not a goal to be approached seriously. After all, we have been told that the EU standard calls for maintenance of loop ppO2 to .03 during dive operations, and a good friend of mine who works on the Mark 16 says that that is the intended goal of the electronics for that particular unit (though mine has NEVER kept it closer than .07-.1 for me), and if you assume a metabolic rate of 1.5 LPM, and an injection rate of .06 l per 1 second injection cycle, you'd have to fire the solenoid around 20 times a minute to maintain the .03 minimum distance from Set-Point

((Math: Diver Consumes .025 Liters Per Second of O2 (1.5 lpm - standard low exertion diver) - therefore, ppO2 could be assumed to drop by the same number. Assume the farthest allowable distance from Set-Point = .03, then you'd have to be injecting .03 of O2 around every third second for a duration (at least in the Hammerhead) of 1/2 second.)).

If you don't mind overshooting your ppO2 by .03, then you can cut the solenoid firing rate in half.

Now, all this is assuming a diver sitting on the bottom not moving very much, or changing depth at all. What happens (as was put to me by some well meaning diver recently) when you have to do an emergency blow from
100 meters? Keeping your loop ppO2 to within .03 of Set-Point is, of course, a joke at that point - keeping yourself from embolizing should be your first concern - but for the sake of argument, lets say that you are doing a faster than normal ascent, how do you design a system to manage your ppO2 and account for differing ascent/descent rates, Interstage Pressure, variable flow rates (because they do change, no matter what anyone says) and even such an obscure issue as Oxygen purity?

Nonetheless - I firmly believe that we can do a much better job of Set-Point Maintenance, if for no other reason than many folks out there feel that it is an important issue, and furthermore, we want to make sure that at ALL depths, and with most any kind of regulator, we minimize the risk of overshooting the ppO2, which is a bigger concern to me personally than maintaining Set-Point to the hundredth of an ATM.

And the answer to this issue I have been told by people smarter than me, is an adaptive algorithm. There are no doubt many kinds of algorithms out there, but there are two we are looking at for the Hammerhead.

The first uses a sort of fuzzy-logic to determine exactly how much O2 to add to the loop. It does not use any input from a Pressure Transducer, so it has no idea how fast the loop ppO2 will change upon injection, because it has no idea where it is in the water column. I don't know for certain, but I believe this is similar to what is being used in the current Inspiration. In this version of the algorithm, the unit fires the solenoid at a pre-determined distance from Set-Point, but only for a very short pulse. It then waits for a given time (usually very short) to determine how much that injection changed the ppO2 output from the Sensors - it then must compute a slope to determine exactly how long the Solenoid should open to move the ppO2 into the acceptable range (in this case, .03 - again, I'll say "HA!" to that).

The second uses input from the Pressure Transducer to determine how long to fire the solenoid. This version is the one I'm favoring right now, since it is information the computer already has at its disposal, and why not use it if it makes it just that much more accurate? This system will know how deep it is, and be able to make assumptions about flow rate/loop volume prior to firing. Of course, all this still has to be adaptive, since a particular divers Interstage Pressure can vary from day to day, or rig to rig. It will use both Duration of fire (Gain) and Frequency of firing to maintain Set-Point. The reason for this is very simple - in an over-the-shoulder CCR, where the injector
is located adjacent to the Intake Port, controlling ppO2 using Gain only is a philosophy I do not agree with. There is, in my opinion, insufficient mixing of the gas taking place. Should you have a situation whereby you flush your loop completely down with Diluent at depth, and then allow the system to begin raising the ppO2 electronically, you have no control during a multi-second fire of the solenoid of your inspired ppO2. The bolus of O2 injected over 10 seconds or more could be as high as 2.5 ATM - far too great in my opinion, even for short duration exposures.

Oh yeah - and while we're on the subject of information the computer has at its disposal: I've received some comments from folks saying that they can "see" themselves breathe while on the Hammerhead, and
that they can also "see" the injection of Oxygen occur by looking at the response of the Sensors on their Primary or Secondary display. The reason for this is simple - our electronics polls the sensors 8 times per second, checking their mV readout which is then compared to the stored slope which was calculated when you did your Calibration - that data is then displayed at the same rate it is sampled, albeit a cycle or two behind - so what you are seeing is real-time ppO2 changes as they happen at the sensor. We do not buffer this output. We have been
asked to do just that, but I have yet to get a good enough argument as to why the end-user (the diver) should not receive the same data the computer is getting from the sensors. The reason I got at the time was that "people will think something is wrong - you're better off just filtering the information they get so you don't get phone calls." On
the one hand, they were right, we have received some calls, but most divers I believe would rather have ALL the information than some buffered version of it. You guys tell me if I'm wrong here.

But back to the Algorithm: Now, remember the variables that we're dealing with here - first off, you've got the accuracy/inaccuracy of the Oxygen Sensors. Then you have the fact that the electronics by their very nature must average the three outputs (or at least the outputs of the cells not voted out) - which in itself could account for
real-world inaccuracies of greater than .03 - then you have the very real Calibration issue, which can be affected by impure Oxygen, or improper flushing, or a sensor that is starting to go stale (and whose curve is losing linearity - something everyone needs to be more concerned about). Add on top of that, variables in Interstage Pressure, Flow Rate, Diver Metabolism and Dive Profile, and you begin to see just how hard it can be to try and manage ppO2 within the tolerances stated above.

That is why - thank god - I do have people working on this issue who are smarter than me. I'll be very interested in seeing just how close they manage to get this to work any better than the method we've been using for years.

Its getting late, and I wanted to get this out before Mole went to bed, but we can discuss this more during the week I'm sure. Like everything else, we're open to ideas and comment. This is an exciting and evolving field, and no one has yet perfected it.

This isn't much of a Mole Report as it is a discussion of some of the logic and philosophy that goes into designing a CCR system. I am certain that others have approached the subject from different viewpoints, but the end result should always be within a fairly narrow range for effective control.

In other news, we're still working on the new electronic package, which has the latest requirement of being able to be used with high-output sensors - some Mark 15 owners have asked us to make it compatible with the R-10 Sensor from Teledyne, and our samples here show that they put out around 35mV in AIR and up to 363 mV in 3 ATM's of O2 (that's enough to start my car!).

I hope that you all read this and think about what I have to say before jumping up and yelling at me. We're not new to this field, and we've got literally hundreds of systems out there that have been working for years and years. Remember, when it all comes down to it, what every rig is, is a bag of gas with O2 put into one end, and CO2 removed at the other - the rest is just plumbing and electronics. Our electronics have been working (with those same solenoids) in Mark 15's, 15.5's 16's, Megalodon's, KISS's, and now Inspirations.

But we never stop learning, and there are always better ways to do things - you just have to remain open to other ideas.

And that is why I truly appreciate everyone's support and input to make this system better than ever.
 

Report 19/5/03

Hey Stephen,

I'm sending you this e-mail from my brother-in-law's AOL account - I'm in California picking up my family (they've been here since May 1st, giving me time to work on Hammerheads and Cis Lunars), and spending a day at the beach.

There is nothing huge to report this week, except that the new Backs (made from 1/4" Lexan) and Stainless Steel Strap Retainers will be ready for me to ship out when I get back to Pennsylvania.

Before I left, I issued yet another Purchase Order for more Hammerhead Parts - we're making 100 more sets to keep up with demand - and part of that is the new electronic boards and software updates.

We have not yet completed any software updates because the new boards will be incorporating some changes which will also require software "handles" on them (such as the new power supply, and the ability to turn on/off some functions on the boards via software switches, or a combination of software and dip switches).  The new software will be backward compatible so that current Hammerhead Systems will be upgradeable.

We're also still collecting data from divers out there to refine the system to their desires.  I've heard recently that some divers would like the LED in the DIVA to be brighter, so we're looking at ways to improve that via software/hardware.  We may elect to change the actual LED's that go into the DIVA, but we need to do some tests before we can make a change which may affect battery life.

Hardware wise, we are making only some minor changes to the Hammerhead design, including some internal dimensional changes to make the unit easier to assemble, and are also giving serious consideration, based upon the input from guys like you, Bob Howell, and Dave Thompson to offering 4 Sensor Ports on the Intake Spindle. This would allow divers to use that option should they decide for themselves that it is better.  Once again, we have conflicting requests/reports on this issue, and the easiest way to deal with these things is to generally give the diver the choice.

Mark Nix sent me a very nice picture of him doing some wreck penetration.  I asked him to post that to the Juergensenmarine list.  It's good to know that the unit is being used in such demanding conditions and is giving the end-user the confidence to perform that kind of work underwater.

As I told you in our phone conversation, we're not done making the Hammerhead better - it is a continuing process which we are committed to.  As we develop new, improved features, we'll make them available to everyone who owns these systems.

I'll be out of the office until Wednesday, when we all return from CA.  After that, it's back to work for the summer, making more Hammerheads, and hopefully catching up with all the Cis Lunar and Mark 15 work that we've got.

I'm not in touch with my e-mail right now, except on a haphazad way (via an AOL connection), so if you have any questions, please wait until Thursday to pose them, as I won't be back in the office working until then.

The next "official" Mole Report will be next Monday, but I'm sure we'll be talking before then.

Hope you are having a great week!

Talk to you soon,

Kevin Juergensen
(via Jose Lamas' computer)

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Mounting the Wrist units. The current units don't have anyway of mounting them provided (bit of an oversight really, and I know Kevin is working on this). I had an old Dive Rite Wrist slate with the 2 extra slates. These were ripped off and 10 minutes with the Swiss army knife Later I had 2 wrist mounts and still the main slate. The Bungee with the slates was perfect for mounting. At first I used Velcro straps to secure the units, but this was a mistake as you cant adjust Velcro wearing gloves and it doesn't take up any slack at depth so it was replaced by knife straps that work well

top...

Here are some quick shots of my unit

My Wrist Units, showing weird reading as they are not plugged in. The top one is the master and is in OC mode, the base is erroring as no cells are connected and the backlight if flashing

My head unit showing the snazzy mowed grass machining effect, and yes I've already been at the Dymo labeller. Note blanking plug for 4th sensor (cable provided) so I can stick my VR3 in there if required

Inside the lid, you can see the easily removable Cell holders, all clearly numbered

Under the cell holder (20 seconds to remove, no tools required) you can see the neat wiring and heavy duty solenoid. The wiring is all gold connectors and easily replaced. All other wiring is sealed into the head making it waterproof. No need to fret if you flood this baby

Close up of the Heavy Duty solenoid (from a Zerox Photocopier!!!!!) and the lovely gold banana plugs. Notice the brown/red/orange top plus which match the wires colours. Only Tom Mount could wire this up wrong 8-)  !!!!!!

The DIVA and heads up display. I made the mistake of putting this in my mouth when I plugged the secondary unit in (with no cells), No way will you miss this alarm (now where's all my fillings gone!!)

The cell plate and the secondary throwing an error (no cells) note the flashing red LED. With both wrists flashing, your nose flashing and teeth trembling, there is no way you are not going to know you have a problem

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ANNOUNCING

The Juergensen Marine Hammerhead™

A New Generation of Diving!

We are very proud to announce the beginning of production of the ALL NEW Juergensen Marine "Hammerhead" replacement Head/Electronics assembly for the Inspiration™ Rebreather!

The first 25 Sets (50 Pieces) have arrived, and are ready for assembly! 12/20/02

For several years, Juergensen Marine, in association with the late Will Smithers of Digital Deep, has been building and installing digital electronics for Closed Circuit Mixed Gas Rebreathers, as well as building and designing new products for the civilian Mark 15/15.5 CCR's used in past years by the US Navy.

We have now applied the knowledge gained over the years to the Inspiration™ rebreather, to come up with the Hammerhead™ Replacement Head and Electronics.

Let's look at what's new about this system:

This is the inside of the new Head. You will notice there is now a solid plate which holds the Sensors. They are facing down, and are well spaced to give plenty of room for installing them into the Replacement Head - Here's a graphic look inside the new head:

In this image, the Head has been graphically removed so you can see the internal "guts" of the Hammerhead, including the Oxygen Solenoid port, the Banana Plug Box and the Three Oxygen Sensors.

 Here's what you don't see above:

We have included a port for a 4th sensor - the diver can use their VR-3 or HUD with a different sensor (say a R-22DHO, or even a K1-D with a proper fitting to hold it) in order to verify the operation of the other three. An innovation for the truly paranoid! Now - you may be wondering, "how hard will it be to open this and change your sensors?...."

With the removal of one nut (the round gray one in the picture above this one) your Sensor Plate is removed.

Now, for the next innovation:

One of the improvements we've made to the original system is how to connect your Oxygen Sensors, yet keep the pathway between them and the Control Electronics dry and free of any water "creep." What we came up with is shown here: the plugs out of the 3 sensors actually lead to micro Banana Plugs which are Gold Plated Brass - the Jacks for these are permanently mounted in the Head and sealed. That means that the wires leading from your sensors have connectors at either end - one end is the Molex that goes into the actual sensor, and the other end is a Gold Plated Brass Banana Plug - if either end of these gets corroded, you toss them out and put in new ones for about $5. No more worries about twisting wires, bad connections to your sensors, or globs of plastic all over the place.

Since the Battery and Control electronics are in the Wrist Unit - we have eliminated much of the clutter found in the original head itself, and consequently have lots of room for the Sensors to stand straight up (as well as adding a 4th). The ports in the top of this unit can be configured in any way that the diver wants to - they come standard with a Primary and a Secondary Display (the Primary controls the Solenoid, the Secondary is a backup Display which is independently wired and powered - for TRUE redundancy) - then they can have either a HUD integrated into the system (via the Internal 3 sensors, the Internal 4th sensor, or an External Sensor, ) - or they can have a connector to go directly to their VR-3 (once again, via the 3 Internal sensors, or 4th Internal sensor).

This is what it looks like with the Fischer Connectors and waterproof Cables attached. The Lumberg (yellow) cable is for the Heads Up Display which mounts on your DSV.

About the Cable... One of the biggest problems with any Electronically Controlled Closed Circuit Rebreather is maintaining electrical continuity, and preventing water intrusion into anything involving current. This has been an issue for every ECCR ever built. The one rig that seems to have solved this issue did so many years ago: the Mark 15/CCR-1000 rigs were equipped with cables and connectors made by Bendix, and later by Amphenol Aerospace. These connectors are 10,000 psi OPEN FACE capable, and the cable they were molded into was sealed on multiple levels. Of course, each connector on a cable cost about a hundred bucks, then add the cable cost and molding, and pretty soon you were looking at a $750 cable. Not too practical outside of the military.

To confront this issue, we contacted a specialty cable company which produces cable for deep water use. We specified an 8 conductor cable that had to have a maximum diameter of .300 of an inch (7.62 mm) and a Bend Radius of 1.5 inches or less (38 mm). It also had to be waterproof.

What we wound up with is a cable that is more than that - a cable which is Depth of Ocean rated, and Helium Leak Proof. A cable which has a PVC jacket which is one of the toughest we have ever seen, yet conforms to our Bend Radius and Maximum Diameter requirements.

Each conductor is coated with void-filling sealant, and each individual STRAND of wire in each of the 8 conductors is also coated with void-filling sealant, making this the most amazing cable we've ever worked with.

A solid PVC core is surrounded by a high-twist archetecture of 8 conductor void filled conductors, ensuring that there are virtually no spaces where water or gas can intrude.

If water gets through this stuff, it must be possessed...

Combine that with the fact that the conductors are channel sealed inside the Head, and then isolated from the control electronics via a Fischer Connector and Receptacle, and you have yourself one of the most leak-proof systems ever made. Period.

Here it is all assembled, and installed into the Inspiration housing. This is now a DIRECT REPLACEMENT for the existing Inspiration Head. To install this system, you simply remove your existing Inspiration Head, complete with all internal and external connections/batteries/electronics/etc, and put them in a closet somewhere safe. You then attach this Replacement Head, hook up your intake/exhaust and Oxygen hoses and DSV and go diving. It is really just that simple. Nothing more to add, nothing to remove from your old Head (except for the O2 Sensors if you want to use them in this new assembly). True "Plug and Play."

A closer view of all the connections and how well they all line up. The complete assembly fits very well and tight into the body of the Rebreather.

But one of the best things about this system is the Displays. Here are all three displays - the Primary on the Left and the Secondary on the Right, as well as the HUD (Mounted on the DSV at the top). TRUE TRIPLE REDUNDANCY in one compact user-friendly unit. If your Primary fails, you have your Secondary Display to tell you what your 3 ppO2 readings are, as well as the HUD to keep you informed of your ppO2 from either all three sensors, or a 4th sensor (your choice). If your Secondary fails, you have your HUD. If your HUD fails, well, then, you really need to book some time with the vicker...

We use identical assemblies for the Primary and Secondary, except they are mirror-image of each other.

The Displays also incorporate the "Varicon™" Convex Lens System, which actually Magnifies the LCD Image for easier viewing. Both Displays come with built-in BACKLIGHT as Standard.

Each of the Wrist Units has an isolated waterproof Battery Housing which contains twin 3.6v Lithium batteries, which cost about $5 each. These are the same batteries used in most computers for PRAM, and as such, are available just about everywhere computers are sold. In our preliminary testing, we found that the batteries in the Primary ran the system, with Solenoid firing, for about 80 HOURS, while the Secondary ran for about 168 HOURS. Clearly, a major improvement over the original system.

The batteries can be removed via a coin-slot cap located on top of the Wrist Unit. This should make changing batteries on a rocking boat a snap.

You will also notice that the top of the Wrist Units (Primary and Secondary) have Wet Switches integrated into them - this means that should you forget to switch on either of your displays, they will do so automatically when you hit the water.

Now for some REALLY Interesting Stuff...

Here you see a side detail of the Primary Electronics Wrist Unit, which also houses the Pressure Transducer (the silver port next to the Fischer Connector). Considering the Primary Electronics also handles Trimix Decompression computing in both Closed Circuit and Open Circuit modes, it makes for an interesting option when...

...you disconnect the cable leading to the Head, Cap the Fischer Bulkhead Connector, and go diving Open Circuit with your Dive Computer still strapped to your wrist...

You now have not only a CCR Controller/Computer, but a perfectly viable OC Dive Computer (or fixed ppO2 CCR Computer) to take with you should you choose to leave your Inspiration® back on the boat!

Is this cool or what?

The unit also has a built-in Trimix Decompression Computer - we are using Buhlmann with Gradient Factors, and are planning on implementing other deco algorithms in the future in order to give users of the Hammerhead® a wide choice of decompression profiles

"DIVA™ System"

Display Integrated Vibration Alarm™

(Patent Pending)

To Be Included With EACH Hammerhead!

ANNOUNCING

The Juergensen Marine DIVA™

A Dynamic New Alarm and Monitoring System for CCR's!

Here's what's new about this system:

The DIVA™ is a Heads Up Display which mounts on your DSV using the supplied bracket. The cable for the module is sealed via a Swagelok connector and runs back to your Hammerhead HUD port.

At the top of the DIVA is an o-ring sealed Tri-Colored Light Emitting Diode, which flashes either Red, Green or Orange depending upon your system's condition, thereby allowing you, the diver, to monitor the status of your system and Oxygen Partial Pressure in a "hands-free" mode - meaning you don't have to constantly look at your Wrist Unit's to monitor your ppO2.

This system works essentially the same as our HUD unit described on our website HERE.

But one of the biggest problems faced by CCR Controllers and Dive Computers today is the issue of Alarms. Most divers hate Alarms - they either beep too loud (and too often), or they don't beep loud enough. Many times, when you hear a beep, it happens to be your dive buddy, or someone else near the dive site even!

Well - we decided to do something about that for CCR divers...

This is the inside of the new DIVA™. You will notice there is a blue cylinder behind the LED in the drawing above. This is a Sealed Vibrating Motor which, when activated, spins an eccentric weight at approximately 7,000 rpm. When attached to the Dive Surface Valve it not only transmits pulses of vibration to the divers mouth (a very sensitive place!) but also sound (described as a "buzzing bee" by our completely unwilling test subjects!) - you feel and hear your alarms at the same time - no more mistaking someone elses alarm for your own!

This is as "personal" as it gets!

In this image, we've cross-sectioned the DIVA™ so you can see the internal guts of the unit laid out. The entire package is 2.35 Inches long. The unit is completely sealed, and maintenance-free. The Body is machined from 316 Stainless with thick walls, so it can take a beating and still keep on ticking!

This is the Bracket which conveniently mounts to the Inspiration DSV via the front screw:

You'll notice the "slot" at the back of the DIVA™ Bracket - this is so that you can adjust the height of the DIVA to suit your own personal preference!

 Like everything we build, we try to keep real divers in mind, and wherever possible give them options to control and adjust their system to their own liking - and we don't have to tell you that giving divers choices as to how their particular machine works is a rather radical concept in dive computers and controllers!

To that end, you will be able to adjust ALL your System Alarms/Notifications which include:

1) LED's located in BOTH Primary and Secondary Displays - On or Off - Divers choice

2) DIVA™ Alarms:

• Low/High Set-Point out-of-range (On/Off)

• Fast Ascent Warning (On/Off)

• Deco Stop Violation Warning (On/Off)

•Hypoxic Mix Alarm (On/Off)

 3) Wrist Unit Alarms: Backlights Flash on/off during Alarm Events which should also notify nearby divers that your system needs attention (in low light conditions, of course) - thereby alerting buddies that you may need assistance.

NOTE: Low (less than .20) and High (greater than 1.8) ppO2 Alarms are NOT able to be turned off by the diver.

Is this cool or what?

Instructions from kevin