This heads up display is a little different from all that went before... The fantastic 3 cell simultaneous monitoring from the shearwater electronics encased in the slim line narked housing and wired via the Narked at 90 3 cell monitoring kits. This means you buy a basic HUD fitted with a Fischer connector as standard. From this point you have a range of options for connection to a Rebreather.
1. If you already have a 3 cell computer cable fitted to your Rebreather you can simply plug it in to the HUD, so the one cable you have can be used for a HUD today or a COMPUTER tomorrow.
2. Buy the HUD and buy the cable system to match the Rebreather you have.
3. Buy the HUD and wire it to your own Rebreather project.
The HUD Monitors three sensors and displays the PPO2 on three LEDs. Each of the sensors corresponds to an LED on the display. Each LED is a dual colour LED. It can show red, green, or orange (both red and green on.) There is a button on the box and it controls the HUD. One push turns it on and one push turns it off. If you turn it on and you get orange flashing for 30 seconds that indicates a low battery. To calibrate, you need to push the button three times within 1 second. It might take a little practice to get this, but it is intended to prevent accidental calibrations. If you successfully do the calibrate sequence, all three lights will come on bright red for 5 seconds. If you don't see that, it didn't get the calibration command.
After you calibrate, each of the sensors should be flashing one orange. That means the PPO2 is between 0.95 and 1.05. The actual value is uses for calibration is .98. If a sensor fails calibration, it will flash one red and one green.
The rest of the flash pattern is:
The number of greens is the number of tenths above 1.0 so three green is 1.3 PPO2. The number of reds is the number of tenths below 1.0 so two red is a PO2 of 0.8
The box contains the processor and battery. To change the battery, remove the screw in cover on the box. The battery should last for months or even years. The battery is a 3.6 V 1/2AA
The unit can be attached onto the breathing hose up beside your head so it is completely out of the way. At the same time, you can reach the button to turn it off and on. Or the HUD display cable is long enough to hide the unit out of the way inside the case of a Rebreather.
we try to hold stock of all products, but if showing out of stock there may be a few days wait while new stock arrives.