rEvo modifications, tweaks and customisations

[stuartv]

Thank you for clarification, @stuartv. I received some responses regarding RMS; hence the disclaimer in my post. If RMS units can utilize the cable there is a lot more value to it.

About adding extra monitor. You make valid points, and I will still argue that a HUD from Fathom, Narked at 90, or other manufacturers is a good value proposition compared to either an expensive Shearwater controller or NERD2.

The Predator controller you've sold recently is no longer supported and any major issue will render the controller useless. A controller under warranty is a much better choice which usually comes with extra cost. HUDs are simple, readily available, and cheaper. The third cable in the bulkhead should not be a major issue - you already have a plug there, so how is having a cable instead of the plug different?

Of course, you don't have to go with HUD. You can go with another monitor. Shearwater Petrel 3 will do and so will DiveSoft (with a special cable).

Part of my point is that I didn't sell my spare controller. Nobody even made an offer. I.e. if you want to spend around a grand, you could potentially get an actual working controller, in good shape, to carry as a backup, instead of some janky HUD monitor.

"no longer supported" is not exactly true and also is FUD. So is "any major issue will render the controller useless".

You can have a major issue with a cheap HUD, too.

The Predator controller still works. I can still have it serviced, as far as I know. I just can't get most stuff on it fixed if it breaks. So, what does "it's not supported" really mean? Not much. It's still a Shearwater. It still will work on any current unit with rMS.

And whether you have a Predator controller or a Petrel 3, it can still die during a trip (as you know all too well), and it doesn't matter which one you have, you're exceedingly unlikely to get it fixed while you're still on your trip. So, with regard to its actual purpose (of saving a trip), the Predator is no worse than a new Petrel 3.

I would sell it only so that I can pile on extra money and get a Petrel 3 controller. And that is really only because "shiny" (and haptic feedback). If I did sell it, I would get the P3 and my Petrel controller would become my backup.

Your "value proposition" puts virtually no "value" on being able to continue your trip using the same setup you started with AND continuing to have 2 functioning devices that are reading your O2 sensors and calculating your deco.

If you have a HUD monitor as your backup to your controller, then when your controller dies, you will be relegated to flying your unit manually for the entire rest of your trip - with no safety "parachute" at all - only one device calculating your "real" deco, and using a standalone computer with a fixed set point as your backup in case your "primary monitor" dies.

For that matter, I only even take a standalone computer in the water on "serious" deco dives. (your definition of "serious" is up to you) The point is, for most of my diving, I have no need for a standalone computer at all. But, if you go with a solution of having 2 monitors as your plan in case your controller dies, then you MUST have a standalone backup computer to go along with that.

So, now your cost comparison is:

1 backup controller

vs

$175 cable, $650 (maybe?) HUD, HUD holder, end caps for the cable (which were stupid expensive last I checked), and an additional tech/CCR-capable dive computer

I don't dive a manual CCR. Why? Because I think a unit with a solenoid is safer. Would I dive with a dead solenoid, in some circumstances (e.g. trip of a lifetime)? Yes. However, I'm going IN with a plan and preparation that will save me from needing to do that in all but the most extremely rare string-of-bad-luck circumstances.

In contrast, you are going in with a plan and preparation to dive an inferior and (in my opinion) less safe configuration in the event of a much more common scenario - one which has already happened to you. For that matter, me, too. The first time I ever got in the pool with my very first rEvo, I flooded my controller immediately. I was an ignoramus and had not put the battery cap back on the controller completely screwed down all the way.

Everybody's "value" is up to them and their wallet. But, this is axiomatic in CCR diving: Don't be cheap.

Changing from a handset controller and a NERD monitor (or equivalent config) to a NERD monitor and a HUD monitor mid-trip is the cheap way out (and, as already observed, not as good or safe).

Anyway, I know I'm not going to change your mind, so this tome on my thoughts on the subject is really intended to provide food for thought for anyone else that may be thinking of following in your footsteps.

You do you.

Peace, out, yo!

 

[stuartv]

The third cable in the bulkhead should not be a major issue - you already have a plug there, so how is having a cable instead of the plug different?

I forgot to address this. I agree that it is not a "major" issue. But, it is not trivial, either, in my opinion.

1) The third port on the rEvo comes plugged from the factory. If it leaks, it will be fixed under warranty. If it doesn't leak, and I never mess with it, then it will probably NEVER leak.

OTOH, if you take that plug out and put your cable in there, then you have created a possibility for a leak. One which will not be covered by any warranty.

2) I have a personal friend who flooded their controller and the head on their (non-rEvo) CCR because they didn't know they got a cut in the sheath of the cable that connected the controller to the head. Water penetrated into the cable and then leached through both ends.

When you add your 3rd cable into your rEvo, you are also adding an increased risk of that happening to you.

And, of course, there's always the chance that you will learn the hard way that you had water going into the end of the cable and corroding the pins (or pin sockets) unbeknownst to you. I mean, maybe you will be diligent and check them every time you post-dive the unit and that will never happen to you. Or maybe you will start out diligently and gradually check them less often. And then find them unusable in the moment that you actually WOULD have a use for them. Like my buddy who carried spare wrist seals everywhere and then when he got to Bikini and actually needed one only then did he discover that they had "rotted" in their bag and were useless.

I remember reading Steve Lewis' book, Six Skills, years ago (I should read it again, now that I have more experience!). One of his points that really stuck with me is (paraphrasing, I'm sure) "don't take anything in the water that you're not going to use."

I think that is an excellent principle to live by. And your third cable seems to be a clear example of violating that principle.

I repeat, yes, these are not "major" issues. But, I think they are not so minor as to just completely ignore them.

 

[mr_v]

@stuartv - dude, I can't read all that, so I had AI summarize it.

Stuart argues against using a HUD monitor as a backup for a CCR controller, citing risks like leaks, cable damage, and controller failure. He believes the Predator controller remains reliable despite being "no longer supported" and advocates for a backup controller instead. Stuart stresses the importance of not being cheap with CCR diving and warns that adding a third cable introduces unnecessary risks, violating the principle of only taking essential equipment underwater.

If that is accurate - all good, you do you ;-)

 

[211ratsbud]

@stuartv - dude, I can't read all that, so I had AI summarize it.



If that is accurate - all good, you do you ;-)

I almost $4!7 my self reading you had ai summarize

 

[lermontov]

A new mod is coming: 4PIN Male - to 4PIN Female cable. Combine it with a piggy tail (R573) and you'll be able to remove your O2 sensor tray. Pics will be in soon. The custom AK4 cable run is almost sold out.

I did that to mine a coupe of years ago - removed all the molex and put in coaxial JJ cells
stripped out the wiring and put in 4 pin wet mates for nerd and controller

 

[Heat Miser]

I don't dive a manual CCR. Why? Because I think a unit with a solenoid is safer.

I agree a solenoid is safer.

However I almost allways dive my unit in parachute mode these days (say 1.2 solenoid setpoint) and manually maintaining a 1.3 setpoint. I've realised that the "booms" are noticed faster, it also forces me to look at the Hud.

As a result I wouldn't think twice about running in manual, with a monitor, if needed. However I would significantly reduce task loading, i.e. no camera, no scooter, limited penetration, limited line laying, limited team leading etc, etc.

It improves the 9V battery duration immensely.

 

[mr_v]

I agree a solenoid is safer.

However I almost allways dive my unit in parachute mode these days (say 1.2 solenoid setpoint) and manually maintaining a 1.3 setpoint. I've realised that the "booms" are noticed faster, it also forces me to look at the Hud.

As a result I wouldn't think twice about running in manual, with a monitor, if needed. However I would significantly reduce task loading, i.e. no camera, no scooter, limited penetration, limited line laying, limited team leading etc, etc.

It improves the 9V battery duration immensely.

Use a 3-button MAV block with a needle valve (Fathom, GBM) instead of the stock rEvo MAV block. Use the needle valve to adjust your O2 addition close to your metabolic rate. You will have to block the CMF orfice or remove the orfice/solenoid combo entirely.

I prefer the hybrid option but run the unit in a parachute mode with 1.0 high setpoint and 1.2 PPO2 loop. All my recent diving has been overhead. Scooter and line work aren't an issue. I can't speak for camera work.

 

[Heat Miser]

Use a 3-button MAV block with a needle valve (Fathom, GBM) instead of the stock rEvo MAV block. Use the needle valve to adjust your O2 addition close to your metabolic rate. You will have to block the CMF orfice or remove the orfice/solenoid combo entirely.

I prefer the hybrid option but run the unit in a parachute mode with 1.0 high setpoint and 1.2 PPO2 loop. All my recent diving has been overhead. Scooter and line work aren't an issue. I can't speak for camera work.

Can you achieve virtually the same thing by upping the IP on the o2 reg and leaving the revo CMF in place? I know you certainly can't do those type of changes mid dive, can you change the Fathom needle valve mid dive?

I don't have a problem doing line work in parchute mode either, however if my controller fails completely and all I've got is a monitor, So no protective floor from the solenoid firing, I am saying I'd prefer to be less task loaded.

 

[mr_v]

Can you achieve virtually the same thing by upping the IP on the o2 reg and leaving the revo CMF in place? I know you certainly can't do those type of changes mid dive, can you change the Fathom needle valve mid dive?

You can change the needle valve setting mid-dive. It works well when you're scootering vs swimming. I did a try-dive with Fathom and was pleasantly surprised by how easy it was to "almost match" your metabolic rate.

 

[mr_v]

rEvo released the M/F 4-PIN cable and a piggy tail as a separate part, R636.

https://www.revo-rebreathers.com/product/r636-4-pin-cable-male-female-including-cable-gland/