Gantenbrink's Robot Discovers Sealed Doors with Copper Fittings

German engineer Rudolf Gantenbrink sends the Upuaut robot up the southern Queen's Chamber shaft. After 65 meters, it encounters a small limestone 'door' with two copper fittings — the first evidence of metal inside the pyramid's shaft system. The copper fittings are later revealed to be 90-degree loops embedded in the limestone, consistent with folded dipole antenna geometry. A second door is found behind the first in 2002, creating a cascaded filter structure. These are not handles. They are antenna elements in a waveguide-fed receiving system aimed at Sirius.