There are many kinds of gauges. There are three types of gauges available: Analog, Digital, and Pneumofathometer models. It is important to choose a gauge that suits your needs in order to ensure a safe dive. Keeping your gauge calibrated is also vital for decompression safety, especially at altitudes.
Analog gauges
Analog gauges used for gauge diving are useful in helping divers determine the depth of water. They work by having a needle pivot around a graduated scale to indicate the depth. These gauges are worn on the wrist or can be integrated into the dive computer. The analog ones may be more reliable than digital gauges, but they are not completely accurate. The advantage to using an analog gauge is that it will never run out batteries.
The gauge's display is easy to read. It offers numerical increments in depth of 10'-40', 20'-40', and 20'-150'. The gauge also features a pressure gauge. It displays pressure from 0 to 5000 psi. The red screen is reserved air while the green screen is main air.
Digital models
Divers desire to be able dive deeper and for longer periods of time, but a digital gauge doesn't allow them to do that. Temperature variations can alter the pressure differential between the gauge (and the ambient water). A mechanical gauge can be safer than an electronics gadget. Not only will it keep track of your dive times and depth but also calculate Nitrogen retention, which can help prevent decompression sickness.
There are two basic types for digital gauge dive computers. The hose connection is a basic method that uses a hose. This hose connects the dive computer with the high-pressure port of the first stage. Wireless mode, however, connects the first stage with an electronic transmitter. You can also find this type of diving computer in console or wrist-mounted models.
Pneumofathometers
Pneumofathometers measure the depth of the air supply to a diver. These devices measure the air pressure at the surface, and indicate the depth in metres or feet. These devices were used to be mounted on an air pump that provided breathing air for standard diving suits. The air supply was completely free-flowing, and there was no back-pressure.
Gauge diving is for divers who wish to use a gauge. A gauge should be able to read between 130 and 160 percent the maximum operating pressure of the diving system. A gauge with this range would suffice for a system that operates at 3,000 psi or more.
Submersible pressure gauges
A submersible pressure gage (SPG), which allows scuba divers keep track of their pressure, is a device used by divers. It can also display the current depth and direction of the diver's movement. The SPG is usually attached to the regulator via a high-pressure hose. This arrangement reduces confusion and prevents the regulator from getting lost. The SPG indicates the remaining air pressure, in pounds per sq inch. It can be used for air supply monitoring while diving.
Scubapro's oil-filled analog depth meter features a Bourdon Tube design. It measures to a depth 200 feet. You can attach the C1 compasses to your console boot for additional versatility. This gauge is best suited for beginners because it is simple and easy to use.
Compass
Easy to read compass is the best for gauge diving. It should have adequate markings to suit your needs and be large enough to be readable underwater. A compass should have a bezel that contains compass headings organized in 30 degree increments, and indicator marks for every five degrees.
A gauge diver's compass should have a side view window to allow them to see the direction it is pointing. This allows the diver to follow the compass' course even in complete darkness.