ASAHI PENTAX S3, Руководство по обслуживанию

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(1) Adjustment of curtain travel speed.
(2) Adjustment of high speed exposure timing (l/1000 sec-1/30 sec.).
(3) Adjustment of slow speed exposure timing (1/15sec.- 1 sec.)
a. CURTAIN SPEED
The curtain travel speed is the time required for the shutter curtains to run through the picture format (36
mm). In this model, the speed is adjusted to be 16.5 +/- 0.3 ms under the ambient temperature of approx.
20
o
C.
The adjustment has to be performed in the following order:
(1
) Set the speed dial (23) at 1/1000.
(2) Disassemble the curtain spring adjust lug (E42) from the curtain spring adjust levers A and B (E92)
(E93), and slowly put the curtain spring back to its original free-of-tension position (in the event it
was wound 2 or 3 times when installing the curtain assembly).
(3) Tension the curtain spring by rotating (E92) 5 times, and (E93) 7 times.
(4) By adjusting the curtain spring, make necessary adjustment of the curtain travel speed so that it
comes within the tolerance of the aforementioned value.
b. HIGH SPEED EXPOSURE TIMING
High speed exposure timing is to be adjusted by changing the width of the slit formed by the 1st and 2nd
curtains. Ease the bulb lever adjust nut (E87) using special tool No. 225K E48-A, and if the screw (20)
is turned clockwise, the exposure timing will be faster; if turned counter-clockwise, the exposure timing
will be slower.
First, adjust the exposure timing for 1/125 sec. (8 ms) and 1/60 sec. (17.8 ms) to their rating or nearest to
it. Then turn the speed dial to 1/1000 sec. (1 ms) and 1/500 (2 ms) for measuring purposes, and repeat
this procedure until satisfactory exposure timing is obtained. Once the above mentioned exposure timing
is determined, exposure timing for the other speeds may be determined automatically by dint of the high
speed cam (E85). Lastly, (E85) should be sealed with red lacquer.
(Diagram 18)
Diagram 18
In the event the shutter curtains, high speed cam and bulb lever parts are not replaced, correct exposure
timing may be obtained merely by adjusting the curtain travel speed, without adjusting the screw (20).
c. IRREGULARITY OF EXPOSURE TIMING
If the exposure timing differs each time the shutter is released, it is called "irregularity of exposure
timing." Strictly speaking, it is extremely difficult to maintain exposure timing entirely free of
irregularity. However, major causes (or irregularity may be traced to the following:
(1) When the top idling gear is oiled or stained.
(2) When the high speed cam (E85) is dusted and or not properly oiled.
(3) When the bottom selector gear (E14) is not properly oiled.
(4) When the 1st, 2nd curtain pinion shafts (E31) (E32), and the shaft receptacle parts of both top and
bottom mec plates (C01) (C02) are not properly oiled.
(5) When the curtain roller metal made of brass (E37) is not properly oiled.
NOTE: No oiling is required where plastic material is used.
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