Electrical interference

[dr.mark]

Hi Group,

When I plug in my dell laptop into my home theatre receiver and it uses the power cord there is a hum through the speakers - when i just run the dell on the battery the hum goes away.

Any suggestions what to do other than keeping the dell unplugged?

Thank you in advance.

Mark Berman

 

[disc]

The most practical thing you can do is make sure the power cords and the signal cords cross each other at a 90 degree angle. This will minimize the mutal inductance which is what's causing the hum.

The best solution is to find a different outlet to plug your laptop into.

 

[SJetski71]

Ya op, try running to different outlets in the home, use an extension cord if necessary, till you're finished troubleshooting that is.

Pretty sure you have what's known as "ground loop", or something similar.