Where is and what type of button(s) are used to control the display?
A. There is one button, inside the case, that is used for all calibration and settings. There are no external switches. The photo below shows the access port to the calibration button. Q. What triggers the auto on/off? A. The On/Off works on PPO2 levels. Q. How does the back light work? A. The backlight is set to either ‘On’ or ‘Off’ in the settings menu. Whenever the unit is active, that setting will be used. Q. What type of battery does it use? Where is it? How do you change it? A. The battery is 1/2AA Lithium, 3.6 volts. It is widely available, and user replaceable. It is fitted inside the digital display. The following pictures show the display with the rear cover removed. The rear cover is removed by undoing four screws. The battery can then be easily changed. You can see the battery, and above it, the calibration/menu pushbutton. Q. What is the battery life with the light on as opposed to off? A. The battery life is as follows: Approx, at 20 degrees C. (68 F.) Standby – 15 months
