I think the unit emits itself somewhere around the 100 MHz range from. My car suppresses although as long as the reception is good, but for example when I travel in the underground car park I hear no radio, but the engine speed as a whistling sound from the speakers. I put out the PowerJolt, the radio plays back music (noisy and quiet - underground stop).
Conclusion:
as charger ok, but not always-infected (as I planned), since otherwise the radio is disturbed