Instrument Function > Modulation > VOR Modulation > VOR Modulation Settings
VOR Modulation Settings

The "VOR Modulation" dialog is opened in the "Mod" function block or using the MENU key under "Mod".

In the upper section, the modulation source is selected and the modulation switched on. The configuration of the selected external and/or internal modulation source is performed in the lower section of the dialog.

State - VOR Modulation

Activates VOR modulation.

Activation of VOR modulation deactivates AM, ILS, Marker Beacon and ADF modulation.

Source selection is disabled in the "LF Output" menu:

Remote command: 
 
Mode - VOR Modulation

Selects the operating mode for the VOR modulation signal.

"Norm"

VOR modulation is active.

"VAR"

Amplitude modulation of the output signal with the VAR signal component (30 Hz signal content) of the VOR signal. The modulation depth of the 30 Hz signal corresponds to the value set under "Var Depth".

"Subcarrier"

Amplitude modulation of the output signal with the unmodulated FM carrier (9960Hz) of the VOR signal. The modulation depth corresponds to the value set under "Subcarrier Depth".

"Subcarrier + FM"

Amplitude modulation of the output signal with the frequency-modulated FM carrier (9960 Hz) of the VOR signal. The frequency deviation corresponds to the value set under "Ref Deviation", the modulation depth corresponds to the value set under "Subcarrier Depth".

Remote command: 
 
Bearing Angle - VOR Modulation

Enters the phase angle between the 30 Hz VAR signal and the 30 Hz reference signal. The orientation of the angle depends on the selected direction.

Remote command: 
 
Direction - VOR Modulation

Enters the reference position of the phase information.

"From"

Selection of the beacon as a reference position. The angle set under "Bearing Angle" corresponds to the angle between the geographic north and the connection line from beacon to airplane.

"To"

Selection of the airplane position as a reference position. The angle set under "Bearing Angle" corresponds to the angle between the geographic north and the connection line from airplane to beacon.

Remote command: 
 
VAR/REF Frequency - VOR Modulation

Enters the frequency of the VAR signal and the REF signal. As the two signals must have the same frequency, the setting is valid for both signals.

Remote command: 
 
VAR Depth - VOR Modulation

Enters the AM modulation depth of the 30 Hz VAR signal. The sum of subcarrier depth, VAR depth and COM/ID and must be smaller than 100 PCT.

Remote command: 
 
Subcarrier Frequency - VOR Modulation

Enters the frequency of the FM carrier.

Remote command: 
 
Subcarrier Depth - VOR Modulation

Enters the AM modulation depth of the FM carrier. The sum of subcarrier depth, VAR depth and COM/ID depth must be smaller than 100 PCT.

Remote command: 
 
REF Deviation - VOR Modulation

Enters the frequency deviation of the REF signal on the FM carrier.

Remote command: 
 
Set to Default - VOR Modulation

Activates the VOR default setting.

Parameter

Value

State

Off

Mode

Norm

Source

Internal

Bearing Angle

0 deg

Direction

From

VAR / REF Frequency

30 Hz

VAR Depth

30 Percent

Subcarrier Frequency

9960 kHz

Subcarrier Depth

30 Percent

REF Deviation

480 Hz

COM/ID State

Off

COM/ID Frequency

1020 kHz

COM/ID Period

9 s

COM/ID Depth

10 percent

Remote command: 
 
COM/ID State - VOR Modulation

Switches on/off an additional communication/identification signal (COM/ID signal).

Remote command: 
 
Show Details - VOR Modulation

Reveals the detailed setting options for the COM/ID signal. Once the details are revealed, the labeling on the button changes to "Hide Details". Use this function to hide the detailed setting options display again. (COM/ID signal).

Remote command: 

n.a.

 
COM/ID Code - VOR Modulation

Enters the coding of the COM/ID signal by the international short name of the airport (e.g. MUC for the Munich airport). (COM/ID signal).

The COM/ID tone is sent according to the selected code (see table of Morse below).The length of the Morse code can be varied. For selection standard time scheme, the selected dot length determines the setting of all other length parameters of the Morse code (dash length, symbol space and letter space) . For selection user time scheme, all length parameters of the code can be set independently.

If no coding is entered, the COM/ID tone is sent uncoded (key down).

Morse Code

Letter

Morse Code

Letter

Morse Code

A

. -

N

- .

B

- . . .

O

- - -

C

- . - .

P

. - - .

D

- . .

Q

- - . -

E

.

R

. - .

F

. . - .

S

. . .

G

- - .

T

-

H

. . . .

U

. . -

I

. .

V

. . . -

J

. - - -

W

. - -

K

- . -

X

- . . -

L

. - . .

Y

- . - -

M

- -

Z

- - . .

Note:

The following values are default values:
  • A dot (.) has a tone duration of 100 ms
  • A dash (-) has a tone duration of 300 ms
  • The time between two tones is 100 ms
  • The time between two letters is 300ms
After each word, a word space is entered. The word repetition rate is 7 words/minute. As the word length can vary between 900 ms and 4500 ms, the word space between the words varies accordingly.

Example: 

ID code = MUC

The word length = 300+100+300+300+100+100+100+100+300+300+300+100+100+100+300+100+100 = 3100 ms

Remote command: 
 
COM/ID Frequency - VOR Modulation

Enters the frequency of the COM/ID signals.

Remote command: 
 
COM/ID Period - VOR Modulation

Enters the period of the COM/ID signal in seconds.

Remote command: 
 
COM/ID Depth - VOR Modulation

Enters the AM modulation depth of the COM/ID signal. The sum of subcarrier depth, VAR depth and COM/ID depth must be smaller than 100 PCT.

Remote command: 
 
COM/ID Time Schema - VOR Modulation

Selects if the set dot length determines the dash length (= three times the dot length) (setting Standard) or if all length parameters can be set independently (setting User). (COM/ID signal).

Remote command: 
 
COM/ID Dot Length - VOR Modulation

Enters the length of a Morse dot by means of seconds. The length of the dash (3xdot), space (=dot) and letter space (=3xdot) is also determined by this entry if time scheme standard is selected.

Remote command: 
 
COM/ID Dash Length - VOR Modulation

(user time schema only)

Enters the length of a Morse dash by means of seconds.

Remote command: 
 
COM/ID Symbol Space - VOR Modulation

(user time schema only)

Enters the length of a symbol space by means of seconds.

Remote command: 
 
COM/ID Letter Space - VOR Modulation

(user time schema only)

Enters the length of a letter space by means of seconds.

Remote command: 
 
Carrier Freq. Knob Step - VOR Modulation

Selects the variation of the carrier frequency via the rotary knob.

"Decimal"

Decimal variation according to the current cursor position.

"Defined"

Variation in predefined steps according to the standardized VOR transmitting frequencies in MHz (see table Table "Standardized VOR transmitting frequencies (MHz) and the associated ICAO channels").

Remote command: 
 
ICAO Channel - VOR Modulation

Selects the ICAO channel, if "Carrier Freq. Knob Step > Defined" is selected.

The individual values in the table cells are:
  • Ch. No. = ICAO channel number
  • VOR Freq. = VOR Interrogation frequency (MHz)
Standardized VOR transmitting frequencies (MHz) and the associated ICAO channels

Ch. No.

VOR Freq.

 

Ch. No.

VOR Freq.

 

Ch. No.

VOR Freq.

 

Ch. No.

VOR Freq.

 

Ch. No.

VOR Freq.

 

Ch. No.

VOR Freq.

17X

17Y

108.00

108.05

 

45X

45Y

110.80

110.85

 

75X

75Y

112.80

112.85

 

89X

89Y

114.20

114.25

 

103X

103Y

115.60

115.65

 

117X

117Y

117.00

117.05

19X

19Y

108.20

108.25

 

47X

47Y

111.00

111.05

 

76X

76Y

112.90

112.95

 

90X

90Y

114.30

114.35

 

104X

104Y

115.70

115.75

 

118X

118Y

117.10

117.15

21X

21Y

108.40

108.45

 

49X

49Y

111.20

111.25

 

77X

77Y

113.00

113.05

 

91X

91Y

114.40

114.45

 

105X

105Y

115.80

115.85

 

119X

119Y

117.20

117.25

23X

23Y

108.60

108.65

 

51X

51Y

111.40

111.45

 

78X

78Y

113.10

113.15

 

92X

92Y

114.50

114.55

 

106X

106Y

115.90

115.95

 

120X

120Y

117.30

117.35

25X

25Y

108.80

108.85

 

53X

53Y

111.60

111.65

 

79X

79Y

113.20

113.25

 

93X

93Y

114.60

114.65

 

107X

107Y

116.00

116.05

 

121X

121Y

117.40

117.45

27X

27Y

109.00

109.05

 

55X

55Y

111.80

111.85

 

80X

80Y

113.30

113.35

 

94X

94Y

114.70

114.75

 

108X

108Y

116.10

116.15

 

122X

122Y

117.50

117.55

29X

29Y

109.20

109.25

 

57X

57Y

112.00

112.05

 

81X

81Y

113.40

113.45

 

95X

95Y

114.80

114.85

 

109X

109Y

116.20

116.25

 

123X

123Y

117.60

117.65

31X

31Y

109.40

109.45

 

58X

58Y

112.10

112.15

 

82X

82Y

113.50

113.55

 

96X

96Y

114.90

114.95

 

110X

110Y

116.30

116.35

 

124X

124Y

117.70

117.75

33X

33Y

109.60

109.65

 

59X

59Y

112.20

112.25

 

83X

83Y

113.60

113.65

 

97X

97Y

115.00

115.05

 

111X

111Y

116.40

116.45

 

125X

125Y

117.80

117.85

35X

35Y

109.80

109.85

 

70X

70Y

112.30

112.35

 

84X

84Y

113.70

113.75

 

98X

98Y

115.10

115.15

 

112X

112Y

116.50

116.55

 

126X

126Y

117.90

117.95

37X

37Y

110.00

110.05

 

71X

71Y

112.40

112.45

 

85X

85Y

113.80

113.85

 

99X

99Y

115.20

115.25

 

113X

113Y

116.60

116.65

   

39X

39Y

110.20

110.25

 

72X

72Y

112.50

112.55

 

86X

86Y

113.90

113.95

 

100X

100Y

115.30

115.35

 

114X

114Y

116.75

116.75

   

41X

41Y

110.40

110.45

 

73X

73Y

112.60

112.65

 

87Y

87Y

114.00

114.05

 

101X

101Y

115.40

115.45

 

115X

115Y

116.80

116.85

   

43X

43Y

110.60

110.65

 

74X

74Y

112.70

112.75

 

88X

88Y

114.10

114.15

 

102X

102Y

115.50

115.55

 

116X

116Y

116.90

116.95

   
Remote command: 
 
EXT AM - VOR Modulation

Switching on/off an external modulation. The external signal is input via the AM EXT connector.

"Off"

Selects the internal modulation source for VOR modulation.

"EXT (MOD AM)"

Selects the external source. The external signal is added to the internal signal. Switching off the internal source is not possible. The external signal is input via the AM EXT connector. The sensitivity is 10 mV per percent modulation depth.

Note: There can be an overmodulation as a function of the level of the external signal without a corresponding caution message being generated. To avoid an overmodulation, the peak value of the external signal is to be delimited corresponding to the sum of the modulation depths of the remaining VOR signal components.

Remote command: 
 

 


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