GPSrChive Discussion Forum

I have used the 66sr a few more times with settings I need for my use:

Backlight brightness 10%
Backlight time out 30 seconds
Battery Save mode on
Wi-Fi off
Bluetooth on
Ant+ Sens off
Compass on
Multi GNSS and Multi Band on
Altimeter – Pressure Trending is ‘Save When On’.
Looking at map screen several times per hour.
100% of the time recording a track.
Occasionally navigating to a geocache using both map and compass.
Reading cache descriptions and logs.
Marking a few waypoints.

The rate of discharge indicates that even with this usage, I should get 12 to 14 hours of battery life. So enough so that I will not have to worry about draining it in a day, or even a couple of days. Because I can almost always charge every night, I am not planning to add a portable charging bank to my backpack.

And FWIW: The following settings indeed gave a discharge rate that computes to about 30 hrs. Interestingly having the compass off seems to make a huge difference, maybe even more than battery saving mode. For me personally, I could not use the unit with these settings and do what I want when hiking, but it did give close to the advertised battery life.

Backlight off except for 2 times checking the battery widget
Backlight Brightness is 10% when on
Trip computer page
Backlight Timeout 15 seconds
Battery Save Mode on
Wi-Fi & Bluetooth both off
ANT+ Sensors are off
Compass off
Multi-GNSS and Multi-Band On
Altimeter - Pressure Trending is 'Save When Power On’

CheminerWill wrote: ↑Sat Feb 13, 2021 9:42 pm The rate of discharge indicates that even with this usage, I should get 12 to 14 hours of battery life.

So, you have not actually tested to see what the true run time is, just performed calculations based on static measurements?

If it is at 50% after 7 hours of use, it is not OK to think that would be approximately 14 hours of battery if continued at the same use? Or is it possibly like my car's gas tank and the closer you get to empty, the faster it drops?

I like to start with a fully charged battery and record a fresh track log at 1 minute intervals until the device shuts off. Then connect to a computer and recover the recorded track to determine the run time for that test. Each track point is one minute of run time.