YSI 30 - Manual (Page 12)

Making Measurements Section 3
YSI, Incorporated Model 30/30M 8
3.4 THE BACKLIGHT
At times it may be necessary to take measurements with the Model 30 in dark or poorly lit areas. To
help in this situation, the Model 30 comes equipped with a backlight which will illuminate the
display so that it can be easily read. To activate the backlight, press and hold down the LIGHT key.
The display will remain lit as long as the key is held down. When you release it, the light goes out to
preserve battery life.