MWA MB 51 Mode D'emploi page 19

3. Guice Rollers
For macnetic film 16 mm the front rings of the three big guide
rollerE (U 1, U 2 and U 3) have to be pushed towards the panel
until they lock. If all three guide rollers are locked in the
right �osition the red LED (16) in the front plate of the
counter lights up.
For ma�netic film 17.5 mm the front rings of the three big
guide rollers have to be pulled away from the panel until they
lock. If all three guide rollers are correctly locked the
yellow LED (17.5) on the front panel of the counter will light
u p .
By setting the guide rollers the speed of film and the sense of
rotaticn of the take-up motor is selected.