Olympus OM-1 Repair Manual page 126

E-30
At the shutter speeds, 1/4 and 1/8:
The S lever escapes from 8606 and the S ankle is engaged. 8605 pushes
the A lever and the L ankle remains unengaged. To differentiate the
shutter speeds of 1/4 and 1/8 from each other, the message is transmitted
from 8575 to the Cam lever to change the operating angle of the G lever.
At the shutter speeds, 1/15 and 1/30:
X
Action is transmitted from 8606 to the S lever and from 8605 to the A
lever, while both the L ankle and the S ankle remain off the engagement.
Without the use of the Ankle, the load is given only by the gears.
Differentiation between 1/15 and 1/30 will be in the same manner as in
the case of 1/1 - 1/8.
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