Davtron M850B User manual

Locking Connector
Positronics MD9F-20J-VL0
NOTE: Keep alive (Pin 9) is only required if CR2032 battery is removed. Flight Time starts
with either Pin 3 or Pin 4 - use only one pin.
DIGITAL CLOCK
M850B
LED Display
GREENWICH MEAN TIME
LOCAL TIME
FLIGHT TIME - Flight Time Alarm
ELAPSED TIME - Count Up, *Countdown, Alarm
COUNT DOWN TIME - Countdown, Alarm
F E A T U R E S
Two button control system is natural and error-
free. Setting operations are identical for both
alarm and time setting. Patent Pending.
Bright sunlight readable LED displays.
Illuminated buttons and annunciators for night
viewing.
Flight Time recorded in hours and minutes or
in hours, tenths, and hundreds.
Serial time data option
Flight time alarm with external output.
Elapsed time with countdown timer with alarm.
Count Down Time with alarm
Crystal precision time reference.
S P E C I F I C A T I O N S
Greenwich Mean Time: 24 hour format.
Local Time: 12 hour or 24 hour format.
Flight Time: records in 99:59 standard, 99:99
hour option
Flight Time Alarm: Full set range flight time.
Elapsed Time Count Up: Starts in minutes,
seconds, then hours, minutes up to 99:59 hrs.
Count Down Time: Settable from one
second to 59 minutes, 59 seconds.
Count Down Time Alarm: Activates at zero
when counting down.
LED Displays: Sunlight readable.
Automatic Dimming.
Battery Type: CR2032.
Polarizing Filter.
Keep Alive Current: .00004 Amps.
Input Current: .2 Amps.
Input Voltage: 14 to 28 Volts
Backlight: 5V, 14V, or 28V - user selectable.
Weight: 5 ounces MAX.
Warranty: 1 year.
5
4
3
2
1
9
8
7
6
- +
+
Alarm Out
Keep Alive .00004A
Ground to start Flight Time
Dimming 5V, 14V or 28V lighting
4V to 28V Starts Flight Time
Serial Clock Data (Option)
14 to 28 Volts, 0.2 Amps (FUSE OR BREAKER AT 1AMP)
Serial Clock Data (Option)
GND
Audio Alarm
(Optional)
.25A
Aircraft Battery
14V - 28V
M850B
1.46
2.90
.125
2.250
+.005-015
4-40 CS
82
° TYP
4 PL.
CHRONOMETER
SELECT CONTROL
CTLSEL
GMT LT FT ET CDT
23:59
2.375
TYP 45 °
4 PL.
M E C H A N I C A L
E L E C T R I C A L
1.875
TYP. 2.238
2.375
TYP.
1.875
FRONT MOUNT
REAR MOUNT
427 HILLCREST WAY
REDWOOD CITY (Emerald Hills), CA 94062
[phone]
www.davtron.com
CHRONOMETER
SELECT CONTROL
CTLSEL
GMT LT FT ET CDT
23:59
M850B
M850B

M850B L S I A ir c r a f t T im e M a n a g e m e n t S y s t e m
Greenwich Mean Time Local Time
Flight Time Elasped Time
CLOCK OPERATION
Normal Operation
The select, SEL, button selects what is to be displayed
in the four digit window and the Control, CTL, button
controls what is being displayed. Pressing SEL
sequentially selects GMT, Local Time, Flight Time,
Elapsed Time, Count Down Time, and back to GMT. The
CTL button starts, stops and resets Elapsed Time when
momentarily pushed. Normal operation of the 850B
cannot accidentally reset time.
Setting GMT
Select GMT for display in the four digit window with the
SEL button. Simultaneously press both the SEL and CTL
buttons to enter the set mode. The tens of hours digit
will start flashing. The CTL button has full control of the
flashing digit and each button push increments the digit.
Once the tens of hour is set, the SEL button selects the
next digit to be set. After the last digit has been selected
and set with the CTL button, a final push of the SEL
button exits the mode. The lighted annunciator will
resume its normal flashing, indicating the GMT clock is
running.
Setting LT
Select Local Time, LT, using the SEL button. Simultane-
ously push the SEL and CTL buttons to enter set mode.
The tens of hours digit will start flashing. The set
operation is the same as for GMT, except that minutes
are already synchronized with the GMT clock. Minutes
can be changed in 15 minute increments for special
time zones.
Setting Flight Time Alarm
When Flight Time, FT, is displayed enter the set mode by
pressing both buttons simultaneously. The alarm time is
entered identically to GMT setting. When the Flight Time
equals the alarm the display will flash and the alarm
output is activated. If FT was not being displayed at the
time the alarm becomes active, the clock automatically
selects FT for display. Pressing either the SEL or CTL
button turns off the alarm. Flight Time is unchanged and
continues counting.
Flight Time Reset
FT must be displayed when resetting. Hold CTL down for
3 seconds or until 99:59 or 99:99 appear on the
display; Flight Time will be zeroed upon the release of
the CTL button. The digits that appear (99:59 or 99:99)
depend on how the clock is programmed - in hours and
minutes or in hours, tenths, and hundredths.
Elapsed Time
Select ET for display. Pressing the CTL button will start
ET counting. Elapsed Time counts up to 59 minutes, 59
seconds, and then switches to hours and minutes. It
continues counting up to 99 hours and 59 minutes.
Pressing the CTL button again stops ET, another press
resets ET. ET has a countdown timer function, repeat
steps for CDT in ET mode.
Count Down Time
Select CDT for display and enter set mode by pressing
both buttons. The Count Down timer can now be set.
Entering the time is identical to GMT time setting. When
the time is entered and the last digit is no longer
flashing the clock is ready to start the countdown.
Momentarily pressing the CTL button starts the
countdown. When count reaches zero the displays flash
and the external alarm is activated. Pressing either SEL
or CTL will deactivate the alarm. CDT continues
counting up. Next press on CTL button to stop counting.
Second press resets CDT to previous set time.
Test Mode
In GMT mode, Hold the SEL button down for three
seconds and the display will indicate 88:88 and activate
all five annunciators.
FIELD OPTION CHANGES
When changes are made the connector of the clock
must be grounded to the soldering iron or warranty may
void.
Local Time: To change from12 hour to 24 hour
format, hold SEL in LT mode for 5 seconds until12 HR
(hour) or 24 HR (hour) flashes, then push CTL for
desired format. Push SEL to exit set mode.
Flight Time: To change from recording in hours,
minutes to recording in hours, tenths, and hundredths,
remove case and jumper OPT-99.
Battery: is a CR2032 coin cell. The recommended
change interval is 5 years. The battery may be removed
permanently if the aircraft battery is connected to the
Keep Alive input (Pin 9). ***Recommend to remove
CR2032 battery if pin 9 is used.
Backlighting SET-UP: Press and hold
down the SEL button on power up to verify backlighting
configuration. Pressing CTL will provide sequence
options 5(Volt), 14(Volt), 28(Volt), and A (Automatic
Sensing). Select backlighting voltage and press SEL
button to confirm. A (Automatic Sensing) will provide
automatic backlighting for input voltage 14 and 28 Volt.
Download installation manual www.davtron.com product page M850B
Count Down Time