Immediately after the scuttling in shallow water much of the ship's superstructure remained above water level, but then over the years the wreck subsided into the muddy bottom and today only the tip of the mast remains above the surface.
The first salvage from the ship was most likely carried out by Royal Navy intelligence teams which recovered the highly advanced Seetakt radar not destroyed in the scuttling. In February, 1940 the wreck was boarded by US Navy sailors from the light cruiser USS Helena.
Seems like a pretty glaring oversight on the Captain's part.
From what I read, the captain was Old School. In all seriousness, he may have thought that after scuttling his ship in neutral territory, stealing the radar was an ungentlemanly thing to do.
It does indeed seem strange that he didn't destroy such a valuable and secret piece of equipment....perhaps there was no time to do it?
Perhaps he thought that the scuttling of the vessel would destroy it as well?