Radio static from phone power cord

I installed a USB charging port for powering my iphone. I am getting static that overrides my squelch setting any time I touch the cord between the phone to the port. Same thing happens if I plug in my Stratus. I tried a clamp on choke with no change. I also tried changing where I was drawing the power from. Any suggestions ? I was thinking of trying RF shielding over the wire, but then I would have to ground it to something. That takes some of the point out of having a USB charging port.

Most likely the USB power converter (12V in to 5V out) is a noisy switching supply and generating a bunch of RF. I would not spend a lot of time trying to fix it unless you are schooled in circuit level EMI countermeasures. I would try another, maybe from a supplier that has tested it in your environment. Maybe try an Apple, they might have at least tried to meet FCC or CE standards.

Here's the one I use and it works well, no noise. I use it for both the iPhone and the iPad.

http://www.amazon.com/SCOSCHE-USBC2...e=UTF8&qid=1399073644&sr=1-1&keywords=scosche

I get the same sort of high pitched whine whenever my iPhone is plugged in and charging while driving my car. I haven't tried to charge the phone in the airplane.

The better quality Belkin ones seem OK. Some others are noisy as and at different frequencies. Which makes the testing more challenging.

My port is a hard wired USB, so nothing other than a plug connection. I don't think it is the issue at all. I believer the problem is the cord. My guess is that the cord is turning me into a broadcast antenna. I'm not very strong with RF theory, but if I am acting as a receiver antenna wouldn't the choke have stopped that? I tried adding three of them! One addition point - I get the noise with and without the ignition on.

My iPhone charges through a utility plug wired to the battery with an inline fuse. When the iPhone is connected to the intercom without charging I have no noise, when charging while connected to the intercom there is a constant squeal.
This audio ground loop isolator from Radio Shack removes the squeal when I am charging my iPhone in the plane: Model: 270-054 | Catalog #: 270-054

We have had these same problems with a power plug to USB adapter. First, make sure you have a good cord (try the original Apple one). Next, try a different USB power plug. The cheap ones are usually the ones that cause problems. Try the one that Stein sells.