Konica Minolta TC-X - Manual (Page 8)

1) When the film speed dial (14) is set at "DX" " the
camera automatically reads the film speed of the film
magazine, so manual film speed setting is unnecessary.
This is only effective with "DX" type films.
2) When non-Ding type film is used, turn the film speed
dial (14) to set the camera for the rating of the film.
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