Even if the machines are on different operating systems, this is dead easy. On the source machine, simply ‘dump’ the repository:
tar zcf reponame.tgz reponame.dump
scp reponame.tgz hostname:/path/to/new/repo
Then login to the new machine, and set up the new repo:
svnadmin create reponame
tar zxf reponame.tgz
svnadmin load reponame < reponame.dump
That’s all there is to it. Then you can of course delete the dump files, the .tgz files, and even the source repo if you are brave.