This set of photos of different AC adapters with the DC connector to the
laptop featured in the foreground is a web based illustration for The Laptop
Repair Workbook. Replacing the connector on an
AC adapter is easy, providing you can obtain one. Some replacement DC connectors
are easily found at the local Radio Shack or electronics hobby store, but
others are proprietary. You can often find the proprietary connectors for
sale on the Internet if you search hard enough, but the easiest source is
to take one off a dead AC adapter. You can often find these for sale on eBay.
The proprietary three contact DC connector shown to the right is from a Dell.
If you have no technician skills, you can usually buy a
replacement adapter from Amazon for around $20.
Both the Dell above and this Sony to the left feature an RF filter on the
cord, very close to the connector. Not all laptop cords feature the filter,
which I believe is to prevent harmonic RF noise from the switching power
supply from entering the laptop. I used to assume that the filter was there
to prevent RF noise from the laptop from escaping via the power cord. From
the standpoint of the laptop user, it doesn't really matter, but I should
probably find a definitive answer some day. The center pin connector the
Sony is using may or may not be proprietary, center pin connectors aren't
that uncommon, but you have to match the pin diameter and the barrel diameter,
and in some cases, the pin length is critical as well.
The Toshiba connector to the right looks like a standard barrel connector,
but it has some subtle flat spots. I suspect it could be replaced with the
right sized generic barrel connector, though it might end up being a little
loose. I can find most barrel shaped connectors for AC adapters in the low
volatage connector drawers at Radio Shack. Finally, the connector at adapter
at the bottom right is a clever 45 W design from Apple. It puts out 24V on
stereo jack style pin. If you have an AC adapter with a failed connector
that you absolutely can't find a connector for, the last refuge is to replace
the power connector inside the laptop with a standard connector.