How to add a repository?

There is a local ubuntu repository that is very fast when updating/installing from it, but I don’t know how to add it, I entered the address through command line using the http:// format the error is “connection refused”. Please help

Menu -> System -> Software Sources shows all repos.
“Local” in synaptic has only your installed software, while new packages come from either downloaded deb packages or the internet, so check the above Application for the speed of your main connections (click on Base - Saucy).

It worked thanks. But its Menu -> Settings -> Software sources. I thought I have to enter it manually