Not sure why no one answered this one for you, so I'll tell you what I know about it.
A scarf joint is usuall made so the length joint itself is 10 to 12 times the thickness of the wood being joined.
Can't say about them all, but my table saw cannot be set to cut at such a shallow angle.
If the wood being scarfed isn't too thick, I suppose you could make some sort of jig to be used with a table saw, as others have done for a circular saw.
Could be that it is less trouble to make the scarf cuts with a plane or sander than it is to make such a jib.
And many seem to prefer any of the variations of the butt joint, anyway.
Hope I didn't simply add to the confusion!
Mike S.
Spring Hill, FL