Yet another iPhone 4 antenna thread!

Discussion in 'iPhone' started by mrochester, Feb 12, 2011.

  1. mrochester macrumors 68000

    Feb 8, 2009
    Hi all

    It's finally occurred to me that the iPhone 4 now has a field test mode which actually gives you a more useful reading when it comes to comparing signal, and as I have another phone sitting right next to the iPhone on the same network, also with a field test mode, I can compare.

    Without touching either device I have 3G signal, and both are around the -97dBM mark.

    When I pick up and hold the iPhone as in this picture http://******************/assets/images/resized/0001/9797/19797v1-max-250x250.jpg (which is how I hold my phone as I'm navigating around it with my right hand) the signal strength goes down to -120dBm, and at this point drops to 'no service'. When I hold the iPhone 4 in the same way, but in my right hand, the signal drops to about -106dBm and retains services.

    When I hold the other device in the same manner (the antenna on this other device is also at the bottom of the phone), the signal strength drops to -103dBm, and it retains service.

    So consistent with Consumer Reports' findings, when held with the lower left seam covered, the iPhone 4 drops considerably more signal that other competing devices.

    In addition, without even holding the iPhone 4, if I put a fingertip over the lower left hand seam, the signal drops to the same -120dBm as when held.

    It really can't be anymore conclusive than that. The left hand seam on the iPhone 4 is a major weakness in the antenna design. The signal deterioration by touching that one spot is so severe that those of us in marginal signal areas will be left with 'no service' if that spot is touched at all.

    Based on the iPhone actual signal to number of bar graphs, the iPhone 4 can go as low as -121dBm before loosing signal. With touching the seam on the lower left causing a loss of 20dBm, this means people who are in the -90dBm or better range probably won't be able to make their phones lose signal completely.
  2. xraydoc macrumors demi-god


    Oct 9, 2005
  3. PNutts macrumors 601


    Jul 24, 2008
    Pacific Northwest, US
    Did not require a response. ;)
  4. Givmeabrek macrumors 68040


    Apr 20, 2009
  5. mrochester thread starter macrumors 68000

    Feb 8, 2009
    Also, with the bumper on, the iPhone 4 performs better than the other device when held. Me thinks it was basically a big mistake for Apple to make the antenna external!
  6. Jordan921 macrumors 601


    Jul 7, 2010
    Bay Area
    You're not telling us anything that we didn't already know. Did you want to feel special by making your own thread?
  7. mrochester thread starter macrumors 68000

    Feb 8, 2009
    I did indeed :). I guess we can safely assume a redesign is on the way with the iPhone 5.
  8. iPhysicist macrumors 65816


    Nov 9, 2009
    Put your index finger close to the to the antenna gate (parallel) and signal will drop too. I just do it for amusement once in a while. Really there is no need for new antenna threads from people who have no clue how things work :rolleyes:

    Enjoy your phone.
  9. sdpics macrumors member

    Jul 15, 2010
    I hope the new antenna design looks something like this

  10. saving107 macrumors 603


    Oct 14, 2007
    San Jose, Ca
    Welcome to 8 months ago, you are a little late to the stating the obvious party.

    FYI, I can't tell you how I know this secret information, but the Packers are going to win the 2011 Super Bowl, place your bets now and thank me later.

Share This Page