2
DIGITAL CLOCK
PILOT'S OPERATING HANDBOOK
MODEL 172RG
SUPPLEMENT
Figure 1. Digital Clock
SECTION 4
NORMAL PROCEDURES
CLOCK AND DATE OPERATION
When operating in the clock mode (see figure 2), the display shows the
time of day in hours and minutes while the activity indicator (colon) will
blink off for one second each ten seconds to indicate proper functioning. If
the RH push button is pressed momentarily, while in the clock mode, the
calendar date appears numerically on the display with month of year to the
left of the colon and day of the month shown to the right of the colon. The
display automatically returns to the clock mode after approximately 1.5
seconds. However, if the RH button is pressed continuously longer than
approximately two seconds, the display will return from the date to the
clock mode with the activity indicator (colon) blinking altered to show
continuously or be blanked completely from the display. Should this
occur, simply press the RH button again for two seconds or longer, and
correct colon blinking will be restored.
NOTE
The clock mode is set at the factory to operate in the 24-
hour format. However, 12-hour format operation may be
selected by changing the position of an internal slide
switch accessible through a small hole on the bottom of the
instrument case. Notice that in the 24-hour format, the
clock mode indicator does not appear.
2
1 July 1979
2
PILOT'S OPERATING HANDBOOK
DIGITAL CLOCK
SUPPLEMENT
MODEL 172RG
SETTING CORRECT DATE AND TIME
The correct date and time are set while in the clock mode using the LH
and RH push buttons as follows: press the LH button once to cause the date
to appear with the month flashing. Press the RH button to cause the month
to advance at one per second (holding button), or one per push until the
correct month appears. Push the LH button again to cause the day of month
to appear flashing, then advance as before using RH button until correct
day of month appears.
Once set correctly, the date advances automatically at midnight each
day until February 29 of each leap year, at which time one day must be
added manually.
1 July 1979
3
LH
Button: Sets date and
ti me of day (when used
with
RH
button).
Center Button: Alternately
displays clock or timer status
RH
Button:
Shows calendar
date momentarily; display
returns to clock mode after
1.5 seconds.
Figure 2. Clock Mode
LH
Button: Resets timer to
"zero".
Center Button:
Alternately
displays clock or timer status
RH
Button:
Alternately starts
and stops timer; timer starts
from any previously accumu-
lated total.
Figure 3. Timer Mode
