caveseeker7
Contributor
Finally, the overdue post about the intro to the Prism Topaz I had. Over a week ago. I tried to get a bit of time on that rig for a while, but the LDS who usually holds them kept moving and cancelling dates. As I wasn't the only one who wanted to get a close-up look and spend some time in the pool with the unit, Peter Ready held the intro himself. What better way to get an intro than from the designer. Shas was there, of course, as was their son and about a dozen curious minds. The latter ranged from complete non-knowledge of rebreathers to Inspiration Instructor. One of the people was there to try a MK16, so there was one of those in addition to the three Prisms.
Meeting time was 9:30, and within 15 minutes we got started. Peter first explained the principle of re-breathing, and went on to O2-CCRs and then mixed-gas units. SCR were just mentioned briefly as they were not the subject of the day, and about a third of the people in the room came from Drägers anyway. Peter went into the diffrerent designs of RBs in general, and the Prism in particular. Including the why rather than just the how when it came to his unit. This is were his giving the intro was most rewarding, as it revealed not just the engineering, but the engineer.
Around 12:30 we broke for a brief lunch, still on RB-related subjects, from RB training to his involvement with the Nautilus.
After that it was pool time. The rigs were all prepped and ready to go, and as there were many of us we didn't get to do that. He did however pull one of the units partially apart to show us most of what needs to be done. The Prism is easy to take apart and access to the internals very good. The bags come off for convenient cleaning. The manual was around since during the lecture for anybody who wanted to look at it. Anyway, the first three divers went into the pool, and with the rigs fitted went through the readout and buttons again. I was in that first group, and down we went. For roughly 40 minutes I scooted forth and back, as well as up and down a couple of times. The ADV works like a charm. I like it's easy response and unobstrusive operation better than APD's new ADV. Early on I started moving about in any possibel orientation to check the breathing resistance while avoiding moisture to run amok in the loop. The transparent scrubber cannister allows the buddy to check on water in the cannister. Sideways and upside down on both horizontal and vertical axis, the Prism breathes very well. Whoever said it doesn't match the Inspiration's ease of breathing is wrong. It pretty much does, even though has a different scrubber design with more absorbent. Breathing resistance is not an issue with the Prism.
The 6-point harness fit well, and balance was good considering that we didn't spend any time on it, rather guessing the amount of lead needed. Only one of the units had the HDD, the other two had wrist-mounted displays. The wrist-mounted primary works very well, easy to read and know. The analog secondary is both easier to see and use than I thought, and responds nicely to changes in the loop. I purposely hyperventilated, and tried to keep up a high breathing rate to see the unit respond. It did so quickly, and very quietly. The gas injection was audible, though. As the pool was not very deep the Prisms were running the low 0.7 ppO2 setpoint, great for manually raising it. So I did, which was easy enough to do and maintain. Here it would be nice to have a readout of all three cells, both to compare their response as well as applying some brain-powered voting logic.
While circleing in a small pool is pretty boring the time went by too fast. But a whole lot of people were waiting their turns, and got them. Including the guy who came for the MK16. And here came the special treat of the day:
I got to dive the MK16.
Shas had told me there might be one, and offered me to take it for a spin. It was an almost original unit, with the stock electronics. The primary LED and the digital run-through display. All in great shape for a rig with more than a decade of operation. It's big. It's heavy, around 70lbs. It's outdated (no on/off switch, unscrew the battery cover and connect the battery - made me wonder: Do they have ignition switches in Hummers, or do they just pull the plugs to shut the engine off ... ). And the back-mounted counterlung isn't even close to shoulder mounted once (although I remember Dolphins feeling worse ... maybe because the MKx have a single bag, so horizontal turns aren't as affected). I went through the same routines as I did with the Prism, flipping and turning, raising and maintaining the elevated setpoint. Quite a bit less convinient, the rear sidemonted manual addition switches. But still managable. And what do I care, I dove a MK16, I dove a MK16, I ... you get the idea. I'm thrilled, it's a legendary unit after all. But, unless you're into collectibels (and I am ), the newer designs are better designs. Aside from any cost or maintenance consideration, they just dive better. That was the consensus between the three of us who had a chance to dive both rigs (the Inspiration instructor being the third one). Afterwards we went back to the classroom, for another Q&A session.
As at the previous RB eve Peter and Shas extended invitations to visit Steam Machines, and look at all the test reports. I want to thank the three Readys for taking the time and making this a memorable, and very enjoyable experience. While playing with the MK16 was the icing on the cake, it was the cake that was excellent. I liked the simplicity of the Prism as much as I enjoyed diving it. Now that was the kind of Monday I like.
Meeting time was 9:30, and within 15 minutes we got started. Peter first explained the principle of re-breathing, and went on to O2-CCRs and then mixed-gas units. SCR were just mentioned briefly as they were not the subject of the day, and about a third of the people in the room came from Drägers anyway. Peter went into the diffrerent designs of RBs in general, and the Prism in particular. Including the why rather than just the how when it came to his unit. This is were his giving the intro was most rewarding, as it revealed not just the engineering, but the engineer.
Around 12:30 we broke for a brief lunch, still on RB-related subjects, from RB training to his involvement with the Nautilus.
After that it was pool time. The rigs were all prepped and ready to go, and as there were many of us we didn't get to do that. He did however pull one of the units partially apart to show us most of what needs to be done. The Prism is easy to take apart and access to the internals very good. The bags come off for convenient cleaning. The manual was around since during the lecture for anybody who wanted to look at it. Anyway, the first three divers went into the pool, and with the rigs fitted went through the readout and buttons again. I was in that first group, and down we went. For roughly 40 minutes I scooted forth and back, as well as up and down a couple of times. The ADV works like a charm. I like it's easy response and unobstrusive operation better than APD's new ADV. Early on I started moving about in any possibel orientation to check the breathing resistance while avoiding moisture to run amok in the loop. The transparent scrubber cannister allows the buddy to check on water in the cannister. Sideways and upside down on both horizontal and vertical axis, the Prism breathes very well. Whoever said it doesn't match the Inspiration's ease of breathing is wrong. It pretty much does, even though has a different scrubber design with more absorbent. Breathing resistance is not an issue with the Prism.
The 6-point harness fit well, and balance was good considering that we didn't spend any time on it, rather guessing the amount of lead needed. Only one of the units had the HDD, the other two had wrist-mounted displays. The wrist-mounted primary works very well, easy to read and know. The analog secondary is both easier to see and use than I thought, and responds nicely to changes in the loop. I purposely hyperventilated, and tried to keep up a high breathing rate to see the unit respond. It did so quickly, and very quietly. The gas injection was audible, though. As the pool was not very deep the Prisms were running the low 0.7 ppO2 setpoint, great for manually raising it. So I did, which was easy enough to do and maintain. Here it would be nice to have a readout of all three cells, both to compare their response as well as applying some brain-powered voting logic.
While circleing in a small pool is pretty boring the time went by too fast. But a whole lot of people were waiting their turns, and got them. Including the guy who came for the MK16. And here came the special treat of the day:
I got to dive the MK16.
Shas had told me there might be one, and offered me to take it for a spin. It was an almost original unit, with the stock electronics. The primary LED and the digital run-through display. All in great shape for a rig with more than a decade of operation. It's big. It's heavy, around 70lbs. It's outdated (no on/off switch, unscrew the battery cover and connect the battery - made me wonder: Do they have ignition switches in Hummers, or do they just pull the plugs to shut the engine off ...
). And the back-mounted counterlung isn't even close to shoulder mounted once (although I remember Dolphins feeling worse ... maybe because the MKx have a single bag, so horizontal turns aren't as affected). I went through the same routines as I did with the Prism, flipping and turning, raising and maintaining the elevated setpoint. Quite a bit less convinient, the rear sidemonted manual addition switches. But still managable. And what do I care, I dove a MK16, I dove a MK16, I ... you get the idea. I'm thrilled, it's a legendary unit after all. But, unless you're into collectibels (and I am ), the newer designs are better designs. Aside from any cost or maintenance consideration, they just dive better. That was the consensus between the three of us who had a chance to dive both rigs (the Inspiration instructor being the third one). Afterwards we went back to the classroom, for another Q&A session.As at the previous RB eve Peter and Shas extended invitations to visit Steam Machines, and look at all the test reports. I want to thank the three Readys for taking the time and making this a memorable, and very enjoyable experience. While playing with the MK16 was the icing on the cake, it was the cake that was excellent. I liked the simplicity of the Prism as much as I enjoyed diving it. Now that was the kind of Monday I like.
