[BackupPC-users] How to schedule a backup

[FleX <fl...@pr...>]

I'm a new BackupPC's user, and I don't understand how can I schedule a 
backup.
For example: I have a notebook , and I'd like to backup ONLY it at 13:00 
every week (incremental) on saturday and every month for a full backup.
How can I do it ?
I find only these option, but I don't know how to set them.
$Conf{FullPeriod} = 6.97;
$Conf{IncrPeriod} = 0.97;

-- 
Best
FleX