Elmo ST-600D Instruction Manual page 13

Optical Sound Film (Model M -O only)
Projection speed selector
24
I
18
Set th e Sound Se lector to "0".
Set t he Sound Se lector to "SILENT".
«;)
Se lect the proper projection speed, either
24 fps (UP) or 18 fps (DOWN).
Important:
Be sure the motor is OFF when changing pro -
jection speed .
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