Curious About Call Time (quasi battery thread)

Discussion in 'iPhone' started by angle, Jul 1, 2009.

  1. angle macrumors regular

    Joined:
    Mar 3, 2008
    Location:
    Michigan
    #1
    Hey Folks,

    Yesterday I was talking on my phone and about 6 minutes in I noticed that my battery indicator (3GS) knocked down a percent. I kept my eye on it, and when I saw it drop another percent I grabbed a screenshot. Did this 4x more times (total of 5 screenshots) during the same call.

    Afterwards, I did a bit of calculating, and came to the conclusion that every 80.5 seconds (on averaging it out) my battery went down a percent. I had 4 out of 5 bars for signal (in a 3G network), was connected to wifi, location services and push both on, brightness around 40 - 45%, bluetooth on (not connected), Gmail fetch 30 min.

    Now, granted, when Apple lists talk time they do so under very controlled circumstances, but when I did the math, I figured that a 25 minute phone call would eat up 18.6% of my battery life. Almost 1/5 of my battery!! Simple math would tell me then that I could get 134 minutes of talk time. A bit shy of the 5 hours (or 300 minutes 3G talk time) that Apple boasts.

    I'm curious if any of you have ever taken the time to calculate anything like this, and what your real world experience with battery life / talk time is. I have to say that when I was in the call and watching the percentage indicator drop...then drop again..and again..and...well, you get the idea, that I was rather alarmed. I have taken the time to fully discharge and "calibrate" my battery...twice...and understand that the services I have on are power intensive. However my 3G wasn't that bad and it's a good deal older.

    Any (CONSTRUCTIVE....notice the emphasis on that) thoughts and opinions are welcomed. I'm just looking for empirical data that can be used to determine various qualities and experiences. Looking forward to your replies!

    P.S. I attached a screenshot of the calcuations I did in Excel. If you see errors, I'd be happy to know!
     

    Attached Files:

  2. Que macrumors 6502

    Joined:
    Apr 5, 2009
    Location:
    UK
  3. angle thread starter macrumors regular

    Joined:
    Mar 3, 2008
    Location:
    Michigan
    #3
    I did most of the math in my head while I was on the call, I just wanted something that I could look at and know for sure that what I was doing was correct. Plus it gave me something to do on a fairly boring phone call ;)
     
  4. angle thread starter macrumors regular

    Joined:
    Mar 3, 2008
    Location:
    Michigan
    #4
    Has anybody else looked at their talk time ratio? Just curious what info is coming out about this and if people are paying attention to it or not.
     
  5. JBaker122586 macrumors 65816

    Joined:
    Jun 21, 2007
    #5
    First of all, you did the math incorrectly.

    For some reason, you decided to exclude the first 7 minutes where you only lost 1% from your calculations. If that's included, you are losing 1% every 2 minutes 24 seconds or so. Meaning a 25 minute phone call only drains 10%, so you get about 250 minutes, or 4 hours and 10 minutes of talk time. This isn't much less than Apple's 5 hours of 3G talk time estimate.

    Also, it's likely your battery was draining faster while on the call because you were staring at the screen and taking screenshots of it, which it then must write to the memory, etc.
     
  6. angle thread starter macrumors regular

    Joined:
    Mar 3, 2008
    Location:
    Michigan
    #6
    If you look carefully, the first time listed is only used as a reference point. All calculations take into account data that I could actually verify. True, my screen was on and I was taking screenshots, but does that really account for that large of a drop in battery life?
     

Share This Page