Reel to Reel video question

[kf4rca]

Type A used by Ampex (VR7800) and IVC. Called type A because it is an alpha wrap around the drum. Tape looped back over itself. One of the reasons for its demise was there were no digital TBCs out at the time. The only TBCs were analog and they couldn't handle the errors coming off the tape.
Type B used by Bosch Fernseh. It is a half wrap around the scanner. Not very popular.
Type C used by Ampex, Sony, Hitachi, RCA. It is an omega wrap around the drum. Sony and Ampex independently developed their formats and found they were very close. They both decided on a compromise and type C was born.