[pct-l] Apple iphone Charging

[Bill Burge]

Awesome info!

I have been looking at the Powerfilm products (I have other things  
that use AA as well as potentially iPhone charging) but don't want to  
buy every one that _might_ work.  I've been doing that for iPhone apps  
(within reason) for testing, but that's a LOT less $$$.

I have gotten devices that would not charge my iPhone 3GS (of iPod  
touch 2G) to work by NOT using the stupid cable that came with it and  
using different cables (Lenmar battery packs are a good example).

With your 3G and the 3-4 day battery life, that must have been casual,  
periodic, use.  If you leave it in a GPS app with tracking (where it  
cannot go to sleep) the longest I have gotten is about 4.5 HOURS.

Also, you can turn off BT, and wifi, and push/pull data; but you  
cannot turn off EDGE without going into "Airplane mode" and that turns  
off the GPS functions as well.  (But the compass in the 3GS continues  
to function.)

BTW:  I LOVE my Otterbox Defender case!  (I got the Black and Yellow  
version, I tried to get my GF to get the pink one and she almost went  
for it, but didn't like the increase in size - though I didn't think  
it was that much)

BillB



On Oct 13, 2009, at 10:35 AM, Tobin Van Pelt wrote:

> I have seen lots of Apple Iphone Charging banter so I though I would
> summarize my experience here:
>
> I was on the PCT for 5 months this year and was able to charge my
> iphone 3G with both a solar panel as well as a backup battery.  People
> should know that Apple uses complex handshaking on some of the USB
> pins to negotiate a charge cycle.  This extends the life of the
> battery and allows it to operate more efficiently.  The key here
> though is that you cannot charge an iphone by just placing a load on
> the power terminals of the USB connectors.  The charger has to be
> engineered for the Apple iphone device or it will not charge.  Many
> companies claim to have chargers for iphones but they do not work
> (amazing how many marketing departments jump to the conclusion that
> since the connectors are the same that is must work).  Beware here
> especially if using one of the newer iphone models such as a 3G
> device ... the electronic logic has changed even further.  (It is my
> judgement that this is not a sell you more stuff strategy ... there
> are actual good engineering design reasons why they use sophisticated
> implementations).
>
> Here is what I had success with on the PCT this year:
>
> 1. Power Film USB solar charger - http://www.powerfilmsolar.com/products/portable_remote/index.php?cat=pr_usb
>
> This solar panel was quite durable, and would fully charge 2 AA
> batteries most days on the PCT (sunny) in about 6-8 hours.  There are
> two concerns here though.  First, the 2 AA battery capacity in the
> solar panel only charges half of a full iphone 3G.  Second, there is a
> logic issue in the DC-to-DC controller of the Powerflim during
> charging for the iphone.  When the AAs get close to depleting, the
> iphone disconnects.  Once this load is removed the batteries rebound
> (voltage comes back up), and then the iphone comes back on pulling the
> voltage down again.  The net effect is at the end of the charge cycle,
> the iphone repeatedly oscillates between charge and no charge.  I was
> able to just watch the charge cycle and disconnect as soon as it got
> to that point to avoid any long term wear and tear.  The iphone
> charges very rapidly off of the AAs so this was never a huge issue.  I
> spoke to the company in detail about this (I was actually testing the
> product for them) and they are aware of this and likely addressing
> this in the future.  I adjusted all settings on my device to maximize
> battery life for the trail (look online there are several overviews on
> how to tune your device for the particular use to extend battery life
> - such as lower screen light, turn off 3G, turn off push/pull of
> email, etc). While using GPS, several iphone apps, and leaving edge
> network on, I never drained a charge faster than once in every two
> days.  So leaving the Power Film on top of my backpack while
> hiking ... I was able to keep my device charged
>
> 2. 3G Juice iphone battery - http://www.3gjuice.com
>
> This guy performed amazing well!  Would fully charge my iphone (and
> even had a little charge left over) from one battery.  Very light
> weight and small.  I carried a couple of these and they performed
> incredibly well in cold and hot temps.  Never had one fail.
>
> In the end - it was more work and more hassle to use the solar panel
> at all.  Because you will be getting resupplies every 3-4 days usually
> - a fully charged phone and two backup 3G Juice batteries get you
> through. The only exception is through the high sierra will you will
> likely want something like the solar panel to get you through.  But
> then again you won't be using phone or SMS so you could just
> completely turn those off and possibly extend the iphone for 4-5 days
> on a full charge (even with a few photos thrown in).
>
> One last thing to think about ... consider getting an otter box case
> defender case for the phone - http://www.otterbox.com/iphone-cases/iphone-3g-3gs/iphone-3g-3gs-defender-case
>
> Water resistant, and shock absorbing this product was amazing as
> well.  I got home, took my iphone out and it looked brand new!
>
> Hope this helps you iphone users on the PCT!
>
> Rocket Man
> PCT-09
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