Cessna 1980 172RG Cutlass Pilot Operating Handbook Download

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DME

PILOT'S OPERATING HANDBOOK

(TYPE 190)

SUPPLEMENT

1. READOUT WINDOW - Displays function readout in nautical miles (

distance-to-station), minutes (time-to-station) or knots (ground speed).

2. R-NAV INDICATOR LAMP - The green R-NAV indicator lamp is provided to

indicate the DME is coupled to an R-NAV system. Since this DME is not factory

installed with an R-NAV system on Cessna airplanes, the R-NAV indicator lamp

should never be illuminated. However, if an R-NAV system is coupled to the DME,
and when in R-NAV mode, the R-NAV lamp will light which indicates that the

distance readout is the "way point" instead of the DME station. The DME can only

give distance (MILES) in R-Nav mode.

3. REMOTE CHANNELING SELECTOR - Two position selector. In the first posi-

tion, the DME will utilize the frequency set by the DME channeling knobs. In the

second position, the MHz digits will utilize the frequency set by the NAV 1 unit's

channeling knobs.

4. WHOLE MEGAHERTZ SELECTOR KNOB - Selects operating frequency in 1-

MHz steps between 108 and 117 MHz.

5. FREQUENCY INDICATOR - Shows operating frequency selected on the DME or

displays remote (REM) flag to indicate DME is operating on a frequency selected

by the remote NAV 1 receiver.

6. FRACTIONAL MEGAHERTZ SELECTOR KNOB - Selects operating frequency

in 50 kHz steps. This knob has two positions, one for the 0 and one for the 5.

7. FRACTIONAL MEGAHERTZ SELECTOR KNOB - Selects operating frequency

in tenths of a Megahertz (0-9).

Figure 1. DME 190 Operating Controls (Sheet 1 of 2)

1 July 1979

PILOT'S OPERATING HANDBOOK

DME

SUPPLEMENT

(TYPE 190)

8. IDENT KNOB - Rotation of this control increases or decreases the volume of the

received station's Ident signal. An erratic display, accompanied by the presence

of two Ident signals, can result if the airplane is flying in an area where two
stations using the same frequency are transmitting.

9. DIM - TST KNOB -

DIM: Controls the brilliance of the readout lamp's segments. Rotate the

control as desired for proper lamp illumination in the function window

(The frequency window is dimmed by the aircraft's radio light dimming
control).

TST (PUSH TEST): This control is used to test the illumination of the readout

lamps, with or without being tuned to a station. Press the control, a

readout of 188 8 should be seen with the mode selector switch in the MIN or

KNOTS position. The decimal point along with 188.8 will light in the
MILES mode. When the control is released, and had the DME been

channeled to a nearby station, the distance to that station will appear. If

the station channeled was not in range, a "bar" readout will be seen (--,- or

10. MODE SELECTOR SWITCH -

OFF: Turns the DME OFF.

MILES: Allows a digital readout to appear in the window which represents

slant range (in nautical miles) to or from the channeled station.

MIN: Allows a digital readout (in minutes) to appear in the window that it will

take the airplane to travel the distance to the channeled station. This time

is only accurate when flying directly TO the station and after the ground
speed has stabilized.

KNOTS: Allows a digital readout (in knots) to appear in the window that is

ground speed and is valid only after the stabilization time (approximately
2 minutes) has elapsed when flying directly TO or FROM the channeled
station.

Figure 1. DME 190 Operating Controls (Sheet 2 of 2)

1 July 1979