Signal de calibration sur la base de temps. La rotation de l'antenne a pour effet de transformer sur l'indicateur panoramique le signal en un cercle, ce qui permet de repérer les distances des échos. 1/9/69

A single calibration blip fed on to the time base of a radial display. The rotation of the time base shows the single blips as a circle on the plan position indicator scope. It may be used to measure range. 1/9/69

The following video provides you with the correct English pronunciation of the word "marqueur de distance", to help you become a better English speaker.