Need RF Quiet USB Power Source

Can anyone recommend a 12 vdc to 5 vdc USB power source I can use to charge an iPhone in flight that won't break squelch on my glider's radio?

-John, Q3

On Thursday, June 26, 2014 7:48:50 AM UTC-7, John Carlyle wrote:
Can anyone recommend a 12 vdc to 5 vdc USB power source I can use to charge an iPhone in flight that won't break squelch on my glider's radio?



-John, Q3

John - I have not had a problem with using a good quality cigarette lighter convertor. Blue Sea sells a panel mounted version, it seems to be shielded in a can (look on Amazon for Blue Sea USB). I had used a potted 12v-5V convertor with my iPhone 4S, you have to trick it by tying the USB data lines together with a 100K resistor. The same trick will not work with the Lightning connector on the iPhone 5S. You need a real cable and a USB supply that responds to the official protocols.

Don't know about your radio, but...

I found a dual USB (1 amp and 2 amp) adapter that plugs into a 12 volt
source in the auto section at Wal Mart. I wired in a 12 volt lighter
plug with a toggle switch to control it and glued it to the side of my
panel. It powers my Streak and has a phone charging cable should I need
it. Cheap and effective.

Dan Marotta

On 6/26/2014 8:48 AM, John Carlyle wrote:
Can anyone recommend a 12 vdc to 5 vdc USB power source I can use to charge an iPhone in flight that won't break squelch on my glider's radio?

-John, Q3

Hi John,

It's not exactly what you're looking for, but the 5V batteries I sell work
great for powering an iPhone.
http://www.cumulus-soaring.com/batterypacks5v.htm

Good Soaring,

Paul Remde
Cumulus Soaring, Inc.
_________________________________

"John Carlyle" wrote in message
...

Can anyone recommend a 12 vdc to 5 vdc USB power source I can use to charge
an iPhone in flight that won't break squelch on my glider's radio?

-John, Q3

Thanks to Jon, Dan and Paul. I asked because the external battery pack I use for my iPhone when I'm not flying creates a whole bunch of noise on my Becker AR4201 radio and on my iCOM A6 when I use it in the glider. I have a 12v adapter for an iPAQ 3950 that makes noise in the glider, too.

I had an old cigarette lighter to iPhone charger. If I can find it, I'll give it a try. Else I guess I'll give the Blue Sea 12V Dual USB Charger Socket a try.

-John, Q3

On Thu, 26 Jun 2014 10:03:09 -0700, John Carlyle wrote:

Thanks to Jon, Dan and Paul. I asked because the external battery pack I
use for my iPhone when I'm not flying creates a whole bunch of noise on
my Becker AR4201 radio and on my iCOM A6 when I use it in the glider. I
have a 12v adapter for an iPAQ 3950 that makes noise in the glider, too.

I had an old cigarette lighter to iPhone charger. If I can find it, I'll
give it a try. Else I guess I'll give the Blue Sea 12V Dual USB Charger
Socket a try.

Most of these converters are switch-mode supplies, so can be a bit RF-
unfriendly. The trick for killing the RF interference is to put the
switch-mode PSU in a Faraday Cage and make sure there are ferrite cores
on all wires coming out of the cage and as close as possible to it.

I used an IPAQ 36xx cigarette lighter adapter because that can supply 1.4
amps at 5v. I took it apart and dug the circuit out of it, soldered 12v
supply leads from it to an XLR socket in place of the cigarette lighter
contacts, connected two pins of a D-9 socket to the 5v end and put the
lot in a small metal box with the connectors mounted in holes cut in the
lid plus a push-fit hole for the PSU's LED, which also helps to mount it:
Pritt pads finish the job of holding it in place and insulating its PCB
from the metal box. The box went behind my panel. I put ferrite cores on
the two leads close to the metal box end.

I've used this for some years to drive satnavs of various sorts without
any noticeable RF interference detected by either my original ATR 500
transceiver or the Dittel KRT2 that has just replaced it - anybody in
need of an ATR 500 in good condition should apply here.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Thanks, Martin.

I found my old iPhone cigarette lighter charger. It puts out enough RF to break squelch on my iCOM A6 if the antenna is within 2 inches of the iPhone. I'll do another test in my glider this weekend to see if the adapter is usable as is before going further.

Your trick of putting the switcher inside a metal box and using chokes on the input and output power lines may be necessary to stifle the switcher...

-John, Q3

As in real estate.... three big things are location, location, location.
Jim

True - but in a glider the location choices are a tad constrained...

-John, Q3

On Thursday, June 26, 2014 6:24:17 PM UTC-4, JS wrote:
As in real estate.... three big things are location, location, location.

Jim

On Thursday, June 26, 2014 7:48:50 AM UTC-7, John Carlyle wrote:
Can anyone recommend a 12 vdc to 5 vdc USB power source I can use to charge an iPhone in flight that won't break squelch on my glider's radio?



-John, Q3

Take a look at the New Trent Power pak http://www.amazon.com/gp/product/B003ZBZ64Q. Use it myself to charge my tablet and IPHONE but can't speak about RF noise though