Although there are digital solutions out there like the DJI Lightbridge, most fpv cameras are analogue. FPVers that like to fly low and hard and fast and around obstacles will ALWAYS have a backup analog system on board, even if their primary video feed is a digital, HD stream. This is due to physics. An analog video stream is inherently "instant' and cannot freeze or lock up, or otherwise just suddenly fail on the operator and leave him blind during moments of flying behind, through, or around obstacles. A digital system, on the other hand, can only handle so many corrupt data packets before it begins to pixellate and/or freeze. As you can imagine, having your video system freeze WHILE you are flying low and fast behind a stand of trees would be incredibly bad.