A vertical blanking interval (VBI) signal testing tool captures, isolates, and analyzes a VBI signal to determine the quality of the VBI signal or signal source. A digitized VBI signal may be received and analyzed according to industry standards. The VBI signal is examined using thresholds, threshold points, and other points as a way of discerning waveforms in the signal and their individual characteristics. Thereafter, deviations of the VBI signal from industry standards are logged or displayed for review. One feature of the tool records captured VBI data to a persistent storage medium, thereby allowing post-processing of the VBI signal at another time and/or another location. An exemplary analysis program can read the recorded VBI data from the persistent storage medium and perform tests to determine the quality of the VBI signal or signal source. VBI signal translations are also contemplated.