A radar fill-level measuring device for measuring a fill level of a fill substance in a container using the travel time principle, comprising a circuit board with a sending/receiving system for sending and receiving high-frequency radar waves, wherein the circuit board has at least two openings, a hollow conductor having at least two lateral edge projections, wherein lengths of the at least two projections are greater than the thickness of the circuit board, wherein the at least two projections are led through the at least two openings, so that the at least two projections extend partially out from a second side of the circuit board, a lid, which is secured to parts of the at least two projections, which extend out from the second side of the circuit board, such that the hollow conductor is secured to the circuit board by means of the lid.