PILOT'S OPERATING HANDBOOK
SUPPLEMENT
SUPPLEMENT
DIGITAL CLOCK
SECTION 1
GENERAL
5
DIGITAL CLOCK
MODEL 172N
The Astro Tech LC-2 Quartz Chronometer (see figure 1) is a precision,
solid state time keeping device which will display to the pilot the time-of
day, the calendar date, and the elapsed time interval between a series of
selected events, such as in-flight check points or legs of a cross-country
flight, etc. These three modes of operation function independently and can
be alternately selected for viewing on the four digit liquid crystal display
(LCD) on the front face of the instrument. Three push button type switches
directly below the display control all time keeping functions. These
control functions are summarized in figures 2 and 3.
The digital display features an internal light (back light) to ensure
good visibility under low cabin lighting conditions or at night. The
intensity of the back light is controlled by the RADIO LT rheostat. In
addition, the display incorporates a test function (see figure 1) which
allows checking that all elements of the display are operating. To activate
the test function, press the LH and RH buttons at the same time.
SECTION 2
LIMITATIONS
There is no change to the airplane limitations when the digital clock is
installed.
SECTION 3
EMERGENCY PROCEDURES
There is no change to the airplane emergency procedures when the
digital clock is installed.
1 July 1979
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