High pitch noise from satellite radio power cord

[wmichladiesman]

I have installed my new satellite radio receiver, but the power cord seems to be causing a high pitch noise. When I touch the cord with my hand the right way or stretch the cord out a little the noise calms down. What is causing this noise? Is there any way to completely eliminate it? The cord is plugged into the lighter.

[PaulD]

your piece of equipment has poor isolation between power ground and signal ground. You might have to cut off the cigatrette plug adapter and wire it to a different spot, or get a power filter to put in line.

[wmichladiesman]

I tested the ground by grounding to a metel bracket underneath the center console. The noise was still there. It would still calm down if I touched the power cord or placed my hand near it.

A power filter was the other thing mentioned. What exactly is this? How much would one cost? Where would one buy it?

If I would connect the satellite receiver to the head unit using an FM modulator instead of the wireless transmitter, would this eliminate the noise?

Another thought would be to purchase a new head unit with an aux input. All and any input in this matter is greatly appreciated, because it will be new and helpful to me and others. I appreciate all your time PaulD, and any more ideas you and others can offer.