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Mark and Space Frequencies

Mark and Space Communication Frequencies are defined by the following formula:

F ("0") = FCarrier + [

F ("1") = FCarrier - [

∆F is the Frequency Deviation.

With Deviation = “0.5” the difference in terms of frequency between the mark and space tones is half the

Baudrate value (

∆F=0.5*BAudrate). When the Deviation = “1” the difference is the Baudrate itself (∆F=

Baudrate). The minimal Frequency Deviation is 600Hz.

Table 3.

Carrier

Frequency

(KHz)

Baud

Rate

Deviation

Exact Frequency [Hz]

(Clock=16MHz)

Carrier

Frequency

(KHz)

Baud

Rate

Deviation

Exact Frequency [Hz]

(Clock=16MHz)

“1”“0”

“1”“0”

60

600

--

82.05

600

--

1

59733

60221

1

81706

82357

1200

0.5

59733

60221

1200

0.5

81706

82357

1

59408

60547

1

81380

82682

2400

0.5

59408

60547

2400

0.5

81380

82682

1

58757

61198

1

80892

83171

4800

0.5

58757

61198

4800

0.5

80892

83171

1

57617

62337

1

79590

84473

66

600

--

86

600

--

1

65755

66243

1

85775

86263

1200

0.5

65755

66243

1200

0.5

85775

86263

1

65430

66569

1

85449

86589

2400

0.5

65430

66569

2400

0.5

85449

86589

1

64779

67220

1

84798

87240

4800

0.5

64779

67220

4800

0.5

84798

87240

1

63639

68359

1

83659

88379

72

600

--

110

600

--

1

71777

72266

1

109701

110352

1200

0.5

71777

72266

1200

0.5

109701

110352

1

71452

72591

1

109375

110677

2400

0.5

71452

72591

2400

0.5

109375

110677

1

70801

73242

1

108724

111165

4800

0.5

70801

73242

4800

0.5

108724

111165

1

69661

74382

1

107585

112467

76

600

--

132.5

600

--

1

75684

76335

1

132161

132813

1200

0.5

75684

76335

1200

0.5

132161

132813

1

75358

76660

1

131836

133138

2400

0.5

75358

76660

2400

0.5

131836

133138

1

74870

77148

1

131348

133626

4800

0.5

74870

77148

4800

0.5

131348

133626

1

73568

78451

1

130046

134928