pescador775
Contributor
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After 29 years with the Scubapro (SOS) DCP I got the bends. Unfortunately, that particular dive I had forgotten to check it before ascending. Turns out that the dial was in the red after a strenuous day of diving. Recovery wasn't fun and took months but wasn't the fault of the equipment. What Fred said: Although the meter allows the dial to enter the red zone for short, non repetitive no- deco dives I always did a hang if the needle got into the red.
The meter is a bourdon tube and does not require calibration unless the needle does not come to rest on the calibration mark which is identified easily by its location and blue color. Failure of the DCP is obvious because the needle does not move, but routine calibration (adjustment of the needle position) is not needed unless the meter has been abused, and as I said, this is easy to perceive. Calibration requires special equipment and cannot be done by the average Joe. The meter movement with its attached bladder and filter have to be removed from the case. The bag, which is filled with a gas, is discarded. The movement has a geared wheel which drives the needle. The position of the gears is adjusted to change the cal point. This is simple but the rest is not. A new bag is glued to the movement and inflated with a special gas, and then the entry point is heated and fused. Later model DCP's give more conservative readings than old models. This difference can be identified by the final resting point of the needle which is to the left of center of the blue line.
I consider the DCP to be more useful than modern computers. However, since the bends incident I dive NITROX and use a REACT Pro. This small device has a graphic which is almost as useful and practical as the DCP.
The meter is a bourdon tube and does not require calibration unless the needle does not come to rest on the calibration mark which is identified easily by its location and blue color. Failure of the DCP is obvious because the needle does not move, but routine calibration (adjustment of the needle position) is not needed unless the meter has been abused, and as I said, this is easy to perceive. Calibration requires special equipment and cannot be done by the average Joe. The meter movement with its attached bladder and filter have to be removed from the case. The bag, which is filled with a gas, is discarded. The movement has a geared wheel which drives the needle. The position of the gears is adjusted to change the cal point. This is simple but the rest is not. A new bag is glued to the movement and inflated with a special gas, and then the entry point is heated and fused. Later model DCP's give more conservative readings than old models. This difference can be identified by the final resting point of the needle which is to the left of center of the blue line.
I consider the DCP to be more useful than modern computers. However, since the bends incident I dive NITROX and use a REACT Pro. This small device has a graphic which is almost as useful and practical as the DCP.
