I'm not sure if this is exactly what has been described above, but I have these pictures of something I've seen done at a guild raising.

Here is a shot of a base plate that has a center piece going up into the post:


Then the base is bolted through these side holes and then plugged over with pegs, I believe:



Then when the frame is raised the post sits on another steel plate in the concrete that has a j-bar or something similar to that in the concrete:



Then the two plates are welded to each other.

I was going to take a series of pictures of the jig/rig the timber framer used to cut the slot in the bottom of the post using a chain saw but my camera malfunctioned and they all came out very blurry....

Hope that helps...

Jim Rogers

Whatever you do, have fun doing it!