Tuesday, 25 June 2013

Greisinger GOX 100 - Oxygen Analyser for Diving

Found this on the internet and decided to give it a go... Its significantly cheaper that the most common analyser ( Analox O2EII Nitrox Analyser ) and only slightly more expensive that a homebrew kit so it seemed a good idea.



Greisinger GOX 100 T Oxygen Meter with Sensor











Details from their website...

Greisinger GOX 100 T Oxygen Meter with Sensor
Highlights & details
  • For gaseous oxygen
  • Automatic temperature compensation for greater accuracy
  • Inc. thermometer
Description
This compact Greisinger GOX 100 T Oxygen Meter with Sensor measures the oxygen concentration in gas mixtures and air. For the best the results the actual measurement of the oxygen takes place at the tip of the included sensor. The unique design of the sensor the device has to be calibrated at regular intervals to obtain accurate measuring values. When the sensor is used up, the device will detect this at calibration and the sensor element hast to be replaced before the start of the next measurement.
By means of the integrated hold-function, the MOD-Display (max. operating depth) and a specialized sensor, it is optimized for the testing of diving gas mixtures (such as NITROX).
Features
  • Min, max value storage
  • Cheap sensor element very easy to replace
  • Sensor evaluation for assessment of the sensor status
  • Simplest calibration on air
  • Configurable automatic OFF function
  • MOD-display (indicates the maximum permitted depth with the measured oxygen mixture).
Included in delivery
  • Sensor with 1 m Cable
  • Hose adaptor
  • T-item
  • 1battery (9V block)
  • O2 oxygen sensor GOEL 370
  • User manual.
The device corresponds to the essential protection ratings established in the Regulations of the Council for the Approximation of Legislation for the member countries regarding electromagnetic compatibility (2004/108/EG). Device meets EN 61326-1:2006, Additional fault: <1%.
Technical data
Accuracy± 0.1 % O2 (± 1 Digt)
Weight150 g
Power supply9 V battery pack
Resolution0.1 % O2
Measurement rangeOxygen concentration: 0.0 – 100.0 % O2
Dimensions(W x H x D) 67 x 106 x 30 mm

I'm glad i made a handsfree bungy attachment so that I can just attach the sensor to the valve, as I've only got two hands.. 







The case is not waterproof. An otterbox/Peli would be better. It survived as I was on a hardboat and there wasn't a great deal of water on the deck... but I can imagine on a Rhib or wet day it won't do unless you put in the cabin/dry bag. I just left it in my mesh bag on the deck.

A nice feature was a hold reading button and a MOD function, basically tells you the MOD of the current reading.

It worked without issues and I was happy for the price..







Tuesday, 28 May 2013

Review 80M Waterproof Underwater 1800 LM CREE XM-L T6 LED Diving Flashlight Torch

Purchased one of these off ebay...



Put a bolt snap on it and went diving... took it to 24m (75ft)., 8 degrees C ( 46 F)..


Results, well it worked during the dive no problems... nice tight beam and about 20-30% brighter that my old UK Light Canon 10W HID. Going by previous lights it looks like ~900 lumens?

However, after the first dive, it had drops of water in the lense... groan...

Stripped it down, left it to dry, greased up the lense O-ring ( which was bone dry) and went back.. this time no problems... 24m depth again. 

One bonus of the strip down is that i've lost the SOS mode. The pill needs to be rotated to match the magnets in the outside ring...I switched the mode selector ring to ON and then rotated the pill till the light came on, then closed it up..

Here are some pictures...










Some closeups of the o-ring sitting on a "ledge".

The lense sits on the o-ring.



I'm sort of happy with it, I'll go through all the O-rings and grease up, making sure all the pieces are tight. Also make sure all the o-ring surfaces and threads are free from loose metal/dirt etc...

Some more pictures...





Some further observations...

The multimode isn't as bad a I first thought.... you don't have to cycle through all the modes every time you switch it on and off.. For instance, if you have it on Full power and just want to turn it off and on again and retain the full power mode, just wait 5 seconds before turning it back on again. If you do it more quickly, it will change mode and go down to the next lower power setting. 

I measured the current on full power, it takes 2.2A with a fresh battery. So at 4.2V its 9.24 Watts.

I had a look at the control board PCB with a view to remove the modes but I didn't understand it enough to come up with a solution. It has one main controller chip ( 8 pin ) in the centre and 2 hall effect sensors on the perimeter of the PCB. It also has space/PCB tracks for 2 more, these are not populated.

So, 4 sensors, each one has a track going into the controller, with +Vcc and GND, leaves two for outputs..

None of the chips had identification numbers on.

There is another 4 pin power device but without taking the PCB out of the base I can't see it or probe it...  

I suppose I could remove the controller chip and put in an ATTiny chip of my own but as i'm going diving next week I want it to be in one piece.

A bit more..

Take care to hold the body of the torch and not the head when you take off the end cap changing batteries OR changing mode/On/Off underwater, the bezel/body connection are too easily loosened and you could create a leak.

Update...

After 14 dives ranging from 41m to 17m in 8 degrees water, I managed to unscrew the bezels by accident and both flooded. Again, dry out and tighten and back to normal. A suggested solution to this was to use a thread lock type product, so i've ordered some Loctite 243 and will see how that goes..

Another Update..

Applied the thread lock ( Loctite 243) to the bezel threads on the head, like so... Tightened the head up. Dived again and didn't flood but only 9m depth dive.... I'll update some more when I get more depth.

Unscrewing it after the dive was not an issue, maybe put a little more on that the small blob in the photo. < Yep works..>...




£3.50 from Amazon.

Update : Bought a third one for the video light project, noticed a slightly different label on the side and it didn't come with the inner plastic battery adapter, otherwise it looks exactly the same. Need to verify its ok with another dive.

Another Update:

Dived to 4m so suspect its ok. I've not got a deeper dive for a month so will feedback then. Tried to disassemble it and noticed: 

The plastic insert/battery adapter was not there, a 16850 battery will still work it just flops about a bit when your tightening up the end, still makes a connection. I had some plastic tubing which I cut down to the same length ( 8cm length, Outside diameter 23mm) as one of the others and it was fine.



The reflector doesn't want to come out nor the LED pcb either. A gently push didn't dislodge it, so might swap the heads around with my older ones to make another video head or give it a whack with a hammer..!
Otherwise this third one, looks ok...

Beam shot :


More shots of the body, the end cap does fit on the head unit... Not sure its water tight but does make a solid seal... Plenty of beam shots on my Vimeo channel...https://vimeo.com/user19212157




Simple goodman handle for the light, found some webbing from an old dive bag, tie wrapped it on. I clip the bolt snap onto my computer bungee to keep it straight. Usually do this once i'm in the water.

Update:

I have three of these now, 2 have glass lenses and 1 has an acrylic lense. None have flooded since I put the loctite thread lock.

1 glass lense one has done 30 dives to a max of 42m ( 137ft).
Another glass one has done 12 dives to a max of 30m ( 98ft)
The acrylic lense version has done 10 dives to 30m.

Run time on an Xtar 2800ma 18650 battery is around 55 mins continuous , which is two dives for me ( its not on all the time).

Two have been converted to Video lights are per my blog.

The only nasty bit is the rotating control ring, this can either go stiff OR very loose... Still works but the spring and steel ball don't like salt water. See other post on my blog for the control ring issues..

The loctite thread lock will need to be applied again soon as I can feel the bezel coming loose again on one of them.

I've not changed the original o-rings. They look awful but so far they have held out, just greased them up.

Another Update:

Someone noticed there was a current drain when in the off position, I checked it with a multimeter and sure enough, looks like around 50mA. I'd not noticed battery going dead when I left them in but I tend to charge them before every dive trip.

I mentioned in another post that the control ring is completely free now i.e. no notch. This mean it slips around quite a bit. The solution is to place a tight bicycle inner tube around it seems to work ok.

Beam shots in the pool:







Saturday, 11 May 2013

Dive Light - Part #9 - Maglite - Another go and still leaks...

So tried the single 3mm O-ring on the front and letting the lense rest on the head. Result was that it leaked in exactly the same way as the last time. Small drops between the lense and the drop-in. Still works but not sure for how long.

This time I got 4 dives out of it at 32m ( 105ft) max, there was a slight flicker from the light but it didn't go out...

The only other thought I have is that the leak is coming from where the body and head screw together..

So might try the liquid casket in there or a slightly bigger O-ring, I know 2.5 is too big and it has a 2mm in there at the moment...Maybe even double up on the 2mm rings..?

Some other issues, the light fell out of the clamp and I nearly lost the goodman handle.

The plastic ring with the magnet slipped off and I found it halfway down the cable.

The maglite holder actually snapped, i needed to wrap an old inner tube around the light to stop it slipping in the holder, this increased the diameter of the maglite and this put too much pressure on the maglite holder, so one side snapped off, groan.





Tuesday, 30 April 2013

Dive Light - New O-rings setup, to cure small flooding..

I'm thinking that, under pressure, the lense might have pushed back into the torch and let water in. I based this on the fact that my lense might of been resting on an o-ring that would have had some give in it.. like so:-


Its a bit difficult to tell what's happening inside but when the o-ring behind the lense, is presented to the torch head, its lining up directly with the head wall, where it goes when I tighten it up, is anybody's guess.. But my thinking is, thats the lense is not resting on a solid/ immovable wall/surface, which could allow it to move under pressure. To make the lense rest on an immovable wall/surface, I changed the design to:


I've removed the inner o-ring to allow the lense to sit on the head wall and have increased the diameter of the outside one to 3mm..

The front 3mm O-ring might be too big as you can see quite a bit of it from the front when tightened up.

I've a 2.5mm section O-ring which I might also try at the front.

The 2.5mm O-ring is too big to go on the body, so the 2mm one is still there.

The lense is still the stepped one, but ideally, it would be better to have one without the step.

When the smaller diameter lense sits inside the head walls.. the bezel can screw further down onto the head which might also help water tightness..maybe!

This is now in testing. Overnight bucket test ok, 4m pool test ok and this weekend 30m dive.


Sunday, 21 April 2013

Disaster Strikes (almost) - Torch has water in it..

Ok, first sea dive of 2013 this weekend.... 27m ( 88ft) in to the English Channel for the Broderick off Hastings... 7 degress water temp.

Torch worked fine for the duration of the dive and out performed the UK Light cannon and Green Force umbilical easily...

Used it throughout the dive with no issues but back on deck noticed a little water on the inside of the lense... Still worked but decided to stop using it there and then.

On opening it at home, the water seems to be between the drop-in and the lense... nothing behind near the electronics or cable gland...

So, it was ok at 15m in the lake... and now at 27m not so good.... I did drag it through the sand and generally not look after it... so not sure if depth or I knocked it... Even so.... not the spec I want..








Friday, 12 April 2013

Rubbish Button SPG

2 years old on a pony... can't read it for the pitting on the window and my eyesight is shot so thats something else wrong with it...


Friday, 5 April 2013

Dive light - Part #9 - New Goodman handle

Upgrade the handle from the lash it up in 5mins to something that looks a little better...

Old:


New:


Parts are:

The maglite holder is a Maglite ASXD021 Auto Clamps Skin for ASXD026E (2 Pieces). Its an American part but they crop up on ebay and Amazon in the UK. It was £7.25.

The Goodman handle was from a chap off  TheDiveForum (TDF) , £16 but you can find them on ebay...

At the moment its attached with a couple of tie wrays until I can find some bolts.

The Maglite slips around in the holder preventing the users from turning the ring which has the magnet on! To get round this I double wrapped some dry suit rubber strips to grip it.. works well...

Some more pictures..







Saturday, 16 March 2013

Dive Compass - Part # 6 - Experiment with Mask

Once mounted, you can truely understand how the software is working and how you as a diver might perceive the signals...

Some observations:

LEDS are blurred so close up to your face but 10mm seperation is enough to determine which one is which... just.

Might have to change the resistors on the LEDS, in low light, they may be too bright... I've put them on analog output pins so I can vary the brightness under software...but its fixed at the moment..

They need to be forward of the mask frame so as to be both seen.

Some colours are more visible that others, red and blue  is good, green less so and the white ( all three colours) can look like red/green on at the same time..

The green level indicator on the LED_2 is a bit of a distraction so I might go back to a single LED.. or use it purely for the waypoint indicator..







Just thinking, I'm going to keep with this format for the moment until I can prove the in-water use of it but saw on another website ( rebreather world) the use of a small OLED display which intrigues me.... maybe mount an OLED display on the mask below the field of view and have the compass/battery at the side of the head...because the tilting of the head to check compass heading is a key feature...