Dell D630 power adaptor interference with usb device

dx052

Recently my power adaptor for my laptop Dell D630 died on me recently . I sourced one recently from a friend to use untill I get a replacement, however when I plug in my usb soundcard into one of the ports
I get some kind of interfernce coming through my speakers. I am not sure why this has happend as the replacement is a Dell and suppossed to be the correct one for this unit. l don't want to buy the offical dell one and have the same issue.

Bowling_4_Gold

You've most likely got a ground loop.

Look at your old power adapter... the cable going from the mains into it, does it have 2 'pins'? Does your friends one have 3 'pins'?

Take a look at this video... http://youtu.be/jSA2F1AwboU

If the above is the case, look for a 2 pin adapter, such as http://www.ebay.co.uk/itm/DELL-PA-10-AC-ADAPTER-POWER-SUPPLY-2-PIN-D620-D630-1520-1525-1545-1735-1535-1555-/400500222633.

dx052

Thanks for that, that was very helpful.

spenderdave

There are a lot of chinese lookalike power adaptors around which do not meet the EMC regulations and which put out loads of rf radiation. Even the ones sold as 'genuine Dell' are cheap imitations. I spent a lot of time filtering the one on my HP laptop and improved it (needed internal modifications so I cannot recommend it unless you are a qualified electronics engineer).