Sears KS-2 - Manual (Page 17)

3. If the (up triangle) (Overexposure mark) or
the (down triangle) (Underexposure mark)
pulsates, you should select another f-stop
number as the exposure is incorrect. If the (up
triangle) or the (down triangle) marks do not
disappear, even after selecting a different f-stop
number, you should select a different shutter
speed.
SHUTTER SPEED REFERENCE TABLE
Lighting conditions
Shutter speed
range
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