Does GLONASS Affect Battery Life?

When I started using the Garmin Oregon 600, I noticed that the battery life was much less than the Garmin GPSMap 62s. I attributed that to the touchscreen or the GLONASS receiver, which the Oregon 600 has but the 62s does not. I just received the new GPSMap 64s, which is the 62s updated to include GLONASS, and that gave me the chance to test the two under similar conditions. Much to my surprise, I found the battery life of the Oregon 600 to be about the same as the 64s, both with GLONASS enabled and disabled. It appears one of the recent firmware upgrades addressed the short battery life of the Oregon 600.

The major drain on the battery on both units is the display backlight. The GLONASS receiver has little effect. So, to extend battery life, set the display backlight timeout to 15 seconds. You can also set battery saving mode on both receivers if you need to leave them on to record a track log. This turns off the display when the backlight goes off. You'll need to tap the power key on the Oregon 600, or any key on the 64s, to turn the display on, so don't enable battery saving if you need to refer to the screen frequently.

Of course, the best power saving method is to turn either receiver completely off and just turn it on momentarily to check your position or save a waypoint. By doing that, you can extend the rated 16-hour battery life of either unit to many days.