Duracell wireless charger, how does it work?

mike

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May 14, 2013, 8:07:15 PM5/14/13

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I picked up a Duracell wireless charger at a garage sale.
Model CP-PPS.
Also known as MyGrid.
Jentec AH 1815-B
Rated 15V at 1A.

It's NOT inductive.
Has alternating metal stripes that supply power to contacts
on the device adapter.

I have the adapter for the ipad, but no ipad.

Thought I'd reverse engineer it to see if I could do anything
useful.

It puts out a square wave from 1V to 3V with a period of about
2milliseconds with a source impedance around 10K.

If you put a resistive load on it, it just drags down the square
wave.

If you put a diode in series with a load of less than 10K,
It powers up and puts out 15V with a narrow periodic sense pulse to
near ground.

So far, so good.

Problem is that most devices need 5V. Not sure why they used
15V.

I was gonna put a zener in series and charge my PDA, until I did
the math and decided I'd need to dissipate 10Watts.

The ipad adapter doesn't look like it has any place big enough for
a switching regulator. I really don't want to tear it apart to
see.

Anybody got insight into how this thing works?

Thanks, mike

Jim Thompson

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May 14, 2013, 8:37:56 PM5/14/13

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On Tue, 14 May 2013 17:07:15 -0700, mike <ham...@netzero.net> wrote:

>I picked up a Duracell wireless charger at a garage sale.
>Model CP-PPS.
>Also known as MyGrid.
>Jentec AH 1815-B
>Rated 15V at 1A.
>
>It's NOT inductive.
>Has alternating metal stripes that supply power to contacts
>on the device adapter.
>

[snip]

Huh? That's not wireless if it has "...metal stripes that supply

power to contacts on the device adapter".

mike

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May 14, 2013, 10:48:15 PM5/14/13

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On 5/14/2013 5:37 PM, Jim Thompson wrote:
> On Tue, 14 May 2013 17:07:15 -0700, mike<ham...@netzero.net> wrote:
>
>> I picked up a Duracell wireless charger at a garage sale.
>> Model CP-PPS.
>> Also known as MyGrid.
>> Jentec AH 1815-B
>> Rated 15V at 1A.
>>
>> It's NOT inductive.
>> Has alternating metal stripes that supply power to contacts
>> on the device adapter.
>>
> [snip]
>
> Huh? That's not wireless if it has "...metal stripes that supply
> power to contacts on the device adapter".
>
> ...Jim Thompson

You need to explain that to the marketing department.

I still need to figger out if there's some magic way to
get the voltage down to 5V or so.

Jim Thompson

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May 14, 2013, 11:02:36 PM5/14/13

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I'd like to find an ordinary phone... no smart-phone BS... that has
inductive charging.

My object is to walk in from the garage, drop my cell-phone in a slot,
keep walking... it'd inductively charge and also talk to the house
desk phones via Bluetooth or WiFi.

(I just Oomatized, and ported both home numbers... completing
tomorrow. I'll call CenturyLink tomorrow and close my account. I'll
now be paying per year what I did pay per month.... for all the bells
and whistles :-)

Edward Lee

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May 15, 2013, 2:53:04 AM5/15/13

to

On May 14, 8:02 pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-

Web-Site.com> wrote:
> On Tue, 14 May 2013 19:48:15 -0700, mike <ham...@netzero.net> wrote:
> >On 5/14/2013 5:37 PM, Jim Thompson wrote:
> >> On Tue, 14 May 2013 17:07:15 -0700, mike<ham...@netzero.net> wrote:
>
> >>> I picked up a Duracell wireless charger at a garage sale.
> >>> Model CP-PPS.
> >>> Also known as MyGrid.
> >>> Jentec AH 1815-B
> >>> Rated 15V at 1A.
>
> >>> It's NOT inductive.
> >>> Has alternating metal stripes that supply power to contacts
> >>> on the device adapter.
>
> >> [snip]
>
> >> Huh? That's not wireless if it has "...metal stripes that supply
> >> power to contacts on the device adapter".
>
> >> ...Jim Thompson
> >You need to explain that to the marketing department.
>
> >I still need to figger out if there's some magic way to
> >get the voltage down to 5V or so.
>
> I'd like to find an ordinary phone... no smart-phone BS... that has
> inductive charging.
>
> My object is to walk in from the garage, drop my cell-phone in a slot,
> keep walking... it'd inductively charge and also talk to the house
> desk phones via Bluetooth or WiFi.
>

Such phone, by definition, would be "smart". In another word, WiFi
phone with VOIP. One of my Android phone is not activated, but for
WiFi access only. All i need is a OOMA like VOIP gateway, then i can
drop my activated phone.

> (I just Oomatized, and ported both home numbers... completing
> tomorrow. I'll call CenturyLink tomorrow and close my account. I'll
> now be paying per year what I did pay per month.... for all the bells
> and whistles :-)

I bet your kids and grand-kids are paying mobile phone bills per
month, what you are paying land-line per year. Such progress
intelligently planned (from phone company commercial).

mike

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May 15, 2013, 4:09:10 AM5/15/13

to

On 5/14/2013 8:02 PM, Jim Thompson wrote:
> On Tue, 14 May 2013 19:48:15 -0700, mike<ham...@netzero.net> wrote:
>
>> On 5/14/2013 5:37 PM, Jim Thompson wrote:
>>> On Tue, 14 May 2013 17:07:15 -0700, mike<ham...@netzero.net> wrote:
>>>
>>>> I picked up a Duracell wireless charger at a garage sale.
>>>> Model CP-PPS.
>>>> Also known as MyGrid.
>>>> Jentec AH 1815-B
>>>> Rated 15V at 1A.
>>>>
>>>> It's NOT inductive.
>>>> Has alternating metal stripes that supply power to contacts
>>>> on the device adapter.
>>>>
>>> [snip]
>>>
>>> Huh? That's not wireless if it has "...metal stripes that supply
>>> power to contacts on the device adapter".
>>>
>>> ...Jim Thompson
>> You need to explain that to the marketing department.
>>
>> I still need to figger out if there's some magic way to
>> get the voltage down to 5V or so.
>
> I'd like to find an ordinary phone... no smart-phone BS... that has
> inductive charging.
>
> My object is to walk in from the garage, drop my cell-phone in a slot,
> keep walking... it'd inductively charge and also talk to the house
> desk phones via Bluetooth or WiFi.

If you're willing to drop it in a slot, just wire up some contacts
and build a slot.

Ordinary wireless phone will do what you want except for the cell part.

>
> (I just Oomatized, and ported both home numbers... completing
> tomorrow. I'll call CenturyLink tomorrow and close my account. I'll
> now be paying per year what I did pay per month.... for all the bells
> and whistles :-)
>
> ...Jim Thompson

I'm in the process of dumping Frontier and using CLEAR for internet.
Bought an obi box that gives me free google voice phone.

I'd still like to make this charger work for my pda.
I can easily fit in the contacts etc, but not much space inside
if I have to add a switcher to get the 15V down to 5V for charging.

amdx

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May 15, 2013, 10:46:40 AM5/15/13

to

On 5/14/2013 10:02 PM, Jim Thompson wrote:
> On Tue, 14 May 2013 19:48:15 -0700, mike <ham...@netzero.net> wrote:
>
>> On 5/14/2013 5:37 PM, Jim Thompson wrote:
>>> On Tue, 14 May 2013 17:07:15 -0700, mike<ham...@netzero.net> wrote:
>>>

> I'll now be paying per year what I did pay per month.... for all the bells
> and whistles :-)
>
> ...Jim Thompson

Note to accounting,
Increase the wine account by the amount saved on phone expenditures.

Mikek :-)

Robert Macy

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May 15, 2013, 10:48:24 AM5/15/13

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On May 14, 8:02 pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-

> | E-mail Icon athttp://www.analog-innovations.com| 1962 |

>
> I love to cook with wine. Sometimes I even put it in the food.

does it have to be open? or, can it just be laid down inside/on a
tray? does that work with it still folded, or whatever phones do
today?

by the way, piece of cake to do the wireless charging, just need a
manufacturer open to add to their product line. Did you ask Samsung?
They're pretty avant garde in their approaches. I've worked with them
before and would like to again.

Jim Thompson

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May 15, 2013, 10:58:10 AM5/15/13

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You got it ;-)

Jim Thompson

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May 15, 2013, 11:00:57 AM5/15/13

to

I like just a simple phone... I'm of the old school, phones are for
talking... this incessant need too surf or tweet or text is NOT my
style.

So I'm in the minority, no one seems to make an inductively charged
talk-only phone :-(

| E-mail Icon at http://www.analog-innovations.com | 1962 |

Martin Riddle

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May 15, 2013, 9:04:46 PM5/15/13

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"Jim Thompson" <To-Email-Use-Th...@On-My-Web-Site.com> wrote
in message news:09u5p854ob0cr809l...@4ax.com...

> On Tue, 14 May 2013 19:48:15 -0700, mike <ham...@netzero.net> wrote:
>
>>On 5/14/2013 5:37 PM, Jim Thompson wrote:
>>> On Tue, 14 May 2013 17:07:15 -0700, mike<ham...@netzero.net> wrote:
>>>
>>>> I picked up a Duracell wireless charger at a garage sale.
>>>> Model CP-PPS.
>>>> Also known as MyGrid.
>>>> Jentec AH 1815-B
>>>> Rated 15V at 1A.
>>>>
>>>> It's NOT inductive.
>>>> Has alternating metal stripes that supply power to contacts
>>>> on the device adapter.
>>>>
>>> [snip]
>>>
>>> Huh? That's not wireless if it has "...metal stripes that supply
>>> power to contacts on the device adapter".
>>>
>>> ...Jim Thompson
>>You need to explain that to the marketing department.
>>
>>I still need to figger out if there's some magic way to
>>get the voltage down to 5V or so.
>
> I'd like to find an ordinary phone... no smart-phone BS... that has
> inductive charging.
>
> My object is to walk in from the garage, drop my cell-phone in a slot,
> keep walking... it'd inductively charge and also talk to the house
> desk phones via Bluetooth or WiFi.

I love my DECT bluetooth link. Works great, but my old razr is power
hungry with the BT radio on.

Cheers

Jim Thompson

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May 15, 2013, 9:32:41 PM5/15/13

to

I've got an old LG Cosmos 2. I leave BT on all the time (Motorola
T325 Bluetooth speakerphone in the car). It goes for nearly a week
before needing a charge. If it had inductive charging I'd keep it
forever.

Robert Macy

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May 16, 2013, 9:12:06 AM5/16/13

to

On May 15, 6:32 pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-

Web-Site.com> wrote:
> On Wed, 15 May 2013 21:04:46 -0400, "Martin Riddle"
>
>
>
>
>

> <martin_...@verizon.net> wrote:
>
> >"Jim Thompson" <To-Email-Use-The-Envelope-I...@On-My-Web-Site.com> wrote
> >in messagenews:09u5p854ob0cr809l...@4ax.com...

> | E-mail Icon athttp://www.analog-innovations.com| 1962 |

>
> I love to cook with wine. Sometimes I even put it in the food.

Bluetooth is built in; the original manufacturer should have built in
wireless charge, too! Since you're not holding the cell phone; there
should be no problem adding something to the phone, right? As I said,
piece of cake to do.

Jim Thompson

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May 16, 2013, 12:09:11 PM5/16/13

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Does anyone have a schematic for these chargers? My particular phone
does have an unusual back with some space that might accommodate some
circuitry.

| E-mail Icon at http://www.analog-innovations.com | 1962 |

amdx

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May 16, 2013, 1:06:49 PM5/16/13

to

I'm with you Jim, I don't want to surf on a small phone screen.
But the world is going to mobile and away from desktops and laptops.
Computer sales are sliding,
"world-wide shipments of laptops and desktops fell 14% in the first
quarter from a year earlier. That is the sharpest drop since IDC began
tracking this data in 1994 and marks the fourth straight quarter of
declines."
From:
http://online.wsj.com/article/SB10001424127887324695104578414973888155516.html

Here's an interesting graph, although ends it in 2011.
Shows amazing growth in iPhone, Android and iPad in a few short years.
> http://www.asymco.com/wp-content/uploads/2012/01/Screen-Shot-2012-01-15-at-1-15-5.54.54-PM.png
Mikek

Jim Thompson

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May 16, 2013, 1:22:42 PM5/16/13

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On Thu, 16 May 2013 12:06:49 -0500, amdx <am...@knologynotthis.net>
wrote:

Yep, I know. All my children and grandchildren seem to have a
gross-sized iPhone or equivalent. My LG Cosmos fits easily in a shirt
pocket, though, in the style of one who used to carry a slip-stick on
his belt, I have holster for it >:-}

| E-mail Icon at http://www.analog-innovations.com | 1962 |

Robert Macy

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May 17, 2013, 10:15:32 AM5/17/13

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On May 16, 9:09 am, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-

Interesting note, for a wireless power transfer you'll see the easiest
way to 'shut off' the spigot of power coming in is to simply short out
the coil destroying its resonance, DO NOT open the coil up like you do
when attached to a voltage supply.

If you're serious about making up a wireless chargning system for your
phone; contact me offline.