USB device interfering AM radio

[Man-wai Chang]

I just discovered this. And I also found that the AC to USB power
adaptor does not have a metal ground pin.

So would this AM interference be gone after getting a better AC to USB
power adaptor?

--
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[Meat Plow]

I just discovered this. And I also found that the AC to USB power
adaptor does not have a metal ground pin.

So would this AM interference be gone after getting a better AC to USB
power adaptor?

The adapter may be a switch mode supply and you are hearing a harmonic
spur of the frequency the supply uses to function on. A switch to non-
switch mode supply would cure your problem.

 

[Man-wai Chang]

My guess(tm) is that you have both the USB power adapter

and the radio plugged into the same outlet or power strip.
Conducted radiation, through the power lines is another
component of the problem. Your radio may be susceptible
to junk pickup from the power lines, or for really cheap
junk, use the power cord as an antenna.
Clamp on ferrite beads (more like ferrite blocks) are
available to block conducted radiation and pickup.

A switch to non-switch mode supply would cure your problem.

Thank you both

--
@~@ Might, Courage, Vision, SINCERITY.
/ v \ Simplicity is Beauty! May the Force and Farce be with you!
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