The XP-H is a compact air-integrated computer that strikes the perfect balance between what you want and what you really need in a dive computer. Most divers will find all the features they need with this single gas computer that’s not much larger than a traditional SPG.
Modes and settings are accessed with just two-buttons. Nitrox can be set from 21% to 100% O2. It offers visual and audible alarms for almost any situation deserving your attention plus a timer for safety stops.
The XP-H uses the ZH-L8 ADT decompression model plus an optional 6-level Micro Bubble program. You also have the option to turn on PDIS – Profile Dependent Intermediate Stops, similar to deep stops but based on your dive profile. Ascent rate is presented numerically as a percentage of the recommended rate, which allows you to see very gradual changes in your ascent speed.
The Logbook offers three pages of data per dive and a history page with cumulative dive stats. The XP-H can store 15 hours of profile information. Dive data can be downloaded to your PC and settings can be changed with Subgear’s DiveLog program that comes on the user manual CD. Along with the usual information the logbook shows your starting time of the dive and the amount of air used.
In Gauge mode the XP-H tracks depth, dive time, PSI, and temp plus max and average depth without deco calculations, there is also a stopwatch function.
We know from experience that computers get easier the more you use them, so we logged a total of 14 dives over six days to get familiar with the XP-H. It was a fast learning curve helped by the accompanying quick start guide and comprehensive user manual CD. The two-button design lets you scroll forward or backward through the main menu. Press and hold the right button to enter a sub-menu or select a setting. The left button takes you back one page and pressing both buttons takes you home.
Underwater we found the display to be clear. The numbers were large enough to read comfortably, especially after we bumped up the contrast setting of the LCD display. The sub-text icons were a bit small and required a little squinting for some of us but that’s a fair trade-off for such a compact data cruncher.
There are three lines of data on the screen. The top shows depth and dive time. The middle shows NDL, and the bottom shows air pressure and O2 exposure. This space also displays ascent rate. A large color-coded nitrogen loading bar graph on the right side can’t be missed, and also functions as a battery level indicator. The battery is a CR2450 that is user replaceable, and should last between 200 to 300 dives. Alternate data such as max depth, temp, and time of day are accessed with the right button. The left button starts your safety stop timer and places a bookmark in your log profile.
After surfacing the XP-H remains in dive mode for 5-minutes, just in case you only surfaced to get your bearings. After that it transitions into surface mode and all surface functions are available.
While using the XP-H we discovered some other interesting features. The backlight has a special setting that turns on and off only when you press the button and won’t time out. This is perfect for night dives where the short duration of most backlights can be frustrating. A small hole in the front of the gauge cover is perfect for attachment to prevent a dangly hose. A special safety mode (SOS) will lock out the computer for 24 hours if a required decompression stop has been missed.
The XP-H has all the features we look for in a computer. One of our testers called the XP-H an “entry level” air-integrated computer but that’s due to the price and not performance. If you are one of the many divers who will never need multiple gasses then what more could you want?