Embodiments include waveguide launchers and connectors (WLCs), and a method of forming a WLC. The WLC has a waveguide connector with a waveguide launcher, a taper, and a slot-line signal converter; and a balun structure on the slot-line signal converter, where the taper is on the slot-line signal converter and a terminal end of the waveguide connector to form a channel and a tapered slot. The WLC may have the waveguide connector disposed on the package, and a waveguide coupled to waveguide connector. The WLC may include assembly pads and external walls of the waveguide connector electrically coupled to package. The WLC may have the balun structure convert a signal to a slot-line signal, and the waveguide launcher converts the slot-line signal to a closed waveguide mode signal, and emits the closed signal along channel and propagates the closed signal along taper slot to the waveguide coupled to waveguide connector.