Thanks for the advice, I liked the idea of making one, but in the end I
parted with some of my hard earned cash and bought one locally similar to
the one that Radio Shack do.

Thanks again Doug and Larry.

Colin.

Snip

Colin Lowe wrote:

Hi all,
I want to make a convertor to step up the voltage from 12vdc to 19vdc to
power my laptop. The mains adaptor I have for the laptop is rated 19vdc
and 3.16A. Thefore I want to step-up the voltage from the 12vdc boat
supply to 19vdc with a capacity of 3.16A max current.
Do you have a circuit or what other options do I have?

Thanks
Colin