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Digital clock (M803 style)

Digital clock (M803 style)

The M803-style round digital clock: an LCD with outside air temperature or bus volts on top and UTC, local, flight time or an elapsed timer below. Its three buttons work like the real ones, including a countdown with an alarm.

Modeled on
Davtron M803-style digital clock / OAT / voltmeter
Category
Flight instruments
Size
1 cell
Version
1.0 · 2026-10-19
Plan
Pro
Simulators
MSFS 2020 · MSFS 2024 · X-Plane 11 · X-Plane 12

Variants

Digital clock (M803 style): M803 style

M803 stylev1.0

This face (the clock instrument's default digital face).

Instrument picker > Clock / timer > FACE > M803 style

Digital clock (M803 style): GT-50 style

GT-50 stylev1.0

Amber LCD timer with Mode / Reset / Action buttons, engine time.

FACE > GT-50 style

Digital clock (M803 style): Color

Colorv1.0

Modern color clock with date, chrono, timer and engine time.

FACE > Color

Digital clock (M803 style): C172 (M803)

C172 (M803)v1.0

This M803 face as in X-Plane 12's 172: silver knobs, lime-green LCD backlit day and night.

FACE > C172 (M803)

Features

  • Top line: O.A.T. in F or C, or bus volts (E)
  • Bottom line: UT (simulator UTC), LT (simulator local), FT (flight time) or ET
  • Flight time starts at takeoff and stops at landing, kept between runs
  • ET counts up (stopwatch) or down (countdown) with an arrow; the mode arrow shows UT / LT / FT / ET
  • Countdown alarm: 00:00 flashes, clicks and buzzes until a button is pressed (up to 15 s)
  • Seven-segment LCD with faint unlit segments; green backlight at night (always on the C172 (M803) face) while the case takes the flood and the glareshield's light
  • Falls back to the device's time when the simulator gives none

On the iPad

  • Top red button (O.A.T. / VOLTS): F, C, volts
  • SELECT: UT, LT, FT, ET; hold in ET to switch counting up / down
  • CONTROL: in ET start/stop, hold to reset; in FT hold to reset the flight time
  • Drag on the LCD in ET down (stopped) to set the countdown, a minute a step
  • Tap elsewhere on the face to change the instrument

Settings

  • Face: Round / C152 / M803 style / GT-50 style / Color / C172 (M803) (instrument picker, under Clock / timer)

Simulator data

What the Hub reads from the simulator for this instrument, and what the instrument sends back. Names are the simulators' own: MSFS SimVars and events, X-Plane datarefs and commands.

Reads

ValueMSFSX-Plane
Outside air temperature (degC)AMBIENT TEMPERATURE (celsius)sim/cockpit2/temperature/outside_air_temp_degc
Main bus voltage (V)ELECTRICAL MAIN BUS VOLTAGE (volts)sim/cockpit2/electrical/bus_volts[0]
Sim UTC time, seconds since midnight (s)ZULU TIME (seconds)sim/time/zulu_time_sec
Sim local time, seconds since midnight (s)LOCAL TIME (seconds)sim/time/local_time_sec
On the ground (1/0) (bool)SIM ON GROUND (bool)sim/flightmodel/failures/onground_any

Add-on aircraft with their own systems may use other variables; the Hub reads the standard ones.

Changes

The instrument's version counts what its faces share (the case, the mechanism, the data, the sounds); a face's own version counts that face alone.

  • 1.0 2026-10-19
    • First numbered version.
Clock / timerVoltmeter