Power Supply Danger
Beware when buying replacement laptop and netbook power supplies!
Sometimes you can source a good replacement laptop power supply off the internet and it will do the job fine, but we have a couple of caveats.
One such power supply was “doing its job”, but after some people were “getting a bit of a tingle” when they touched the netbook that it was plugged into we got the oscilloscope onto it and found that it was putting about 90v ac onto the chassis of the netbook. If in doubt, don’t buy low cost power supplies as this one was potentially lethal.
Another problem that we have found on a few occasions is that either none of the choice of adapters quite fits or the socket on the laptop has been damaged. If the plug doesn’t make a really good connection with the socket then you get “resistive heating” which can melt the plug and / or the socket and can burn you.