b. Replacing pointer.
Caution: This is a very delicate operation. It must be attempted in
the field only when absolutely necessary and only by competent per-
sonnel.
(1) Remove the cover and plastic window as described in a (1) to
(3) above.
(2) Using a very small screw driver or the blade of a pen knife,
loosen the pointer clamping screw and remove the pointer, being care-
ful not to bend the pointer shaft.
(3) Carefully place a new pointer on the pointer shaft and rotate
it around the shaft until it reads the pressure (at least within a half
millibar) as determined by a mercury barometer. Gently press the
pointer down flush with the end of the pointer shaft.
(4) Tighten the pointer setscrew, again being careful not to bend
the pointer shaft.
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