Today's Message Index:
----------------------
1. 05:04 AM - Spring Cleaning (Harley)
2. 06:01 AM - Re: USB (rvtach)
3. 08:05 AM - Re: USB (Noel Loveys)
4. 08:51 AM - Re: USB (Christopher Cee Stone)
5. 02:14 PM - Re: USB (Robert L. Nuckolls, III)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
Only a few days left on these items I've put on eBay. They are
all selling, but some are going for ridiculously low prices! How
about a good O-235 starter for $10, for example? Even if you
don't need one of these items, having a spare around, especially
at these prices, is not a bad idea.
Oh... for those who were interested, the guitar is sold!
You can see the rest of them here: http://tinyurl.com/7darnnb
Harley Dixon
Long EZ N28EZ
Hangar 29
Canandaigua Airport
Canandaigua, NY
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
Sam-
I did something similar. I wanted a USB charging port and had looked at the possibility
of canabalizing a car charger- just a few dollars plus the time and energy
to tear it apart and (hopefully) make it suitable for installation in an
aircraft. I finally bought a DC-DC converter from these guys for less than $20:
http://www.current-logic.com/dcdc_converter_by_power.php?plow=1&phigh=99
Turned out to be a pretty nice looking, well built device that is ready to install.
Saved myself some $time$ since electronics are not my forte' and repackaging
electronic components is not a skill I care to learn right now.
Cheers!
--------
Jim McChesney
Tucson, AZ
RV-7A Finishing Kit
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=368590#368590
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
What a great idea!
Wish I=99d thought of it.
Noel
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of James
Kilford
Sent: March 14, 2012 10:24 PM
Subject: Re: AeroElectric-List: USB
You will need to regulate to 5V. The specs for USB and in particular
charger ports are specific. If you want a quick, cheap & effective
workaround, why not buy a car USB charger and cannibalise?
http://www.amazon.com/HTC-T-Mobile-myTouch-Car-Charger/dp/B002TOKTHO/ref=
sr_1_9?s=wireless
<http://www.amazon.com/HTC-T-Mobile-myTouch-Car-Charger/dp/B002TOKTHO/ref
=sr_1_9?s=wireless&ie=UTF8&qid=1331772672&sr=1-9>
&ie=UTF8&qid=1331772672&sr=1-9
is for sale at $0.01 + $2.95 shipping!
On 14 March 2012 22:47, Sam Staton <pj260@bellsouth.net> wrote:
<pj260@bellsouth.net>
I would like to set up a mini-USB bus in my panel. I have obtained 4 USB
connectors from L-com.com, and they appear to be ready to connect. My
question to the brain-trust here is this - do I need to setup a 5V
regulator, or can I just wire them up to ship's power (+12V)? Of course,
the last thing I want to do is destroy the expensive iPhone & iPad I
want to connect to them! Any assistance will be gratefully accepted.
Thanks in advance!
Sam Staton
RV6 - getting close!
-
ric-List"
target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
MS -
k">http://forums.matronics.com
e -
-Matt Dralle, List Admin.
t="_blank">http://www.matronics.com/contribution
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
USB charging.
USB ports do not just provide 5v for the device under charge. The USB port
provides intelligent charging in so much as it poll s the device and
produces a charging current that is tailored to the battery state. In most
cases the default charge (no polling response) is trickle charge. This can
be as low as 20mA which will not run and charge some devices.
See:
http://www.eetimes.com/design/power-management-design/4237849/USB-battery-charging--it-s-harder-than-it-looks?cid=NL_Medical&Ecosystem=medical-design
Chris Stone
RV-8
Newberg, OR
> *
> *
>
> ** **
>
> You will need to regulate to 5V. The specs for USB and in particular
> charger ports are specific. If you want a quick, cheap & effective
> workaround, why not buy a car USB charger and cannibalise?****
>
> ** **
>
>
> http://www.amazon.com/HTC-T-Mobile-myTouch-Car-Charger/dp/B002TOKTHO/ref=sr_1_9?s=wireless&ie=UTF8&qid=1331772672&sr=1-9
> ****
>
> ** **
>
> is for sale at $0.01 + $2.95 shipping!****
>
> ** **
>
> ** **
>
> I would like to set up a mini-USB bus in my panel. I have obtained 4 USB
> connectors from L-com.com, and they appear to be ready to connect. My
> question to the brain-trust here is this - do I need to setup a 5V
> regulator, or can I just wire them up to ship's power (+12V)? Of course,
> the last thing I want to do is destroy the expensive iPhone & iPad I want
> to connect to them! Any assistance will be gratefully accepted. Thanks in
> advance!
>
>
> Sam Staton
> RV6 - getting close!
>
>
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
At 10:50 AM 3/15/2012, you wrote:
USB charging.
USB ports do not just provide 5v for the device under charge. The
USB port provides intelligent charging in so much as it poll s the
device and produces a charging current that is tailored to the
battery state. In most cases the default charge (no polling
response) is trickle charge. This can be as low as 20mA which will
not run and charge some devices.
. . . the operative word here is "SOME". It is
true that some devices are supplied with a dedicated
charger.
The "wall charger" illustrated in the first link . . .
Emacs!
Is not a 'smart' charger. It's merely a 5V power supply
that includes a couple of bias networks intended to convice
the powered device that there is a 'real' USB client on
the other end of the cable . . . silent but real.
Some power supplies do not include these resistors. My
Motorola mobile phone rejects some of the USB power
sources I've attempted to use but most 'foreign' chargers
work just fine with this particular phone.
Without a doubt, any USB port on a computer used to
power up an external device is nothing more than a limited
current, 5V power supply with a couple of terminals for
bi-directional serial communications. USB devices intended
to work in concert with industry standard devices contain
identification data that is automatically offered to
your computer which will then search the list of presently
installed drivers that will provide a common language for
accomplishment of a task. This is why your computer automatically
recognizes many common tools like mice, keyboards, imaging
devices, etc. . . . while others don't wake up the computer
until a unique driver is installed.
POWERING up a remote device, CHARGING that device's
battery and COMMUNICATING with that device are separate
and only slightly related tasks. I've designed several
USB interface devices where the +5V from the host computer
is not even hooked up. Current demands for my product
were too great to push off onto the computer.
None of my projects included batteries . . . but if they
DID . . . and assuming I wanted to utilize an external
+5 volt source to CHARGE those batteries . . . all the
intelligence needed would be built into MY device. I'm
aware of no USB port on any PC that offers any measure of
control of the 5V supply line. In fact, given the huge
constellation of specialized battery charging protocols,
it would not make sense to integrate such features into
a PC.
So you buy a battery powered device that comes with a
USB cord and perhaps a 'wall wart' for charging. All
bets for universal connection with other USB 'power
sources' is problematic. There are third party
chargers (like IGO) with specialized 'tips'
that not only brings +5 (or some other voltage) to the
portable device -AND- no doubt does some things to
spoof the portable into believing the foreign source
of power is 'friendly'.
Emacs!
I probed the 6 interface pins in this adapter (which
works with my mobile phone) and found THREE resistors.
No doubt they are necessary to effect a friendly
interconnection with the phone. There are only 3 wires
between the adapter and the power supply so at least
one and perhaps two of those resistors are used to
"talk to the power source" with the remainder used
to placate the mobile phone.
Bottom line:
There's an old adage that says "If it looks like
a duck, quacks like a duck and walks like a duck . . .
it must be a duck."
The context of "USB" port discussions here on the List
is to provide a miniature version of the legacy cigar
lighter receptacle wherein power provided is not
ship's bus but a clean, regulated source of 5 volts.
These 'ducks' do indeed have common appearance and
they WALK like other ducks . . . but they don't TALK
like the others . . . and don't need to.
One could consider adapting a compact, multi-port
device like this . . .
Emacs!
mounted on the panel and then wired to a 5V
DC-to-DC down converter . . .
Emacs!
Available for a few dollars . . . postage
paid.
Some caveats:
Given that this $3 device powers devices with much
greater $cost$ from a very robust energy source, it
might be prudent to craft some sort of OV protection
system. These are switchmode power supplies that
can either run un-regulated -OR- fail with a mode
that applies full bus voltage to your USB cord
connected precious.
These are switchmode power supplies. They MIGHT
pose a risk to other devices on the panel . . . most
notably receivers. I've had several commercial-off-
the-shelf cigar lighter adapters that would tear up
AM radio reception under certain conditions.
Should it happen that your particular device balks
for lack of characterization (like an IGO A32 tip)
then you might have to buy the tip designed to
'talk' to your device and adapt or clone it into
your airborne, USB connector based POWER distribution
system.
Bob . . .
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|