Mode specifications

 

FT4

Sequence time:
Duration of transmission:
User information, per transmission:
Message CRC:
Code:
Total bits sent per transmission:
Modulation:
Channel bandwidth:
Total occupied bandwidth:
Single tone duration:
Information tones:
Synchronization:

 

 

 

FT8 v2

Sequence time: 15s
Duration of transmission: 12.64 s
User information, per transmission: 77 bits
Message CRC: 14 bits
Code: LDPC(174,91)
Total bits sent per transmission: 174 bits
Modulation: 8-FSK, continuous phase
Channel bandwidth: 6.25 Hz
Total occupied bandwidth: 50 Hz
Single tone duration: 0.16 sec
Information tones: 58
Synchronization: seven channel, 7x7 Costas array, 3x7 tones, channels: 4,2,5,1,7,6,3

 

 

FT8 v1

Sequence time: 15s
Duration of transmission: 12.64 s
User information, per transmission: 75 bits
Message CRC: 12 bits
Code: LDPC(174,87)
Total bits sent per transmission: 174 bits
Modulation: 8-FSK, continuous phase
Channel bandwidth: 6.25 Hz
Total occupied bandwidth: 50 Hz
Single tone duration: 0.16 sec
Information tones: 58
Synchronization: seven channel, 7x7 Costas array, 3x7 tones, channels: 3,6,7,1,5,2,4

 

JT65

Sequence time: 60s
Duration of transmission, approximately: 46.81 sec
User information, per transmission: 72 bits
Code: Reed Solomon (63,12)
Total bits sent per transmission: 378 bits
Modulation: 65-FSK, continuous phase
Channel bandwidth, approximately: 2.69 Hz
Total occupied bandwidth, approximately: 174.95 Hz
Single tone duration, approximately: 0.372 sec
Information tones: 63
Synchronization: single channel, 63 tones

 

JT9

Sequence time: 60s
Duration of transmission: 48.96 s
User information, per transmission: 72 bits
Code: convolutional, constraint length K=32, rate r=1/2, zero tail
Total bits sent per transmission: 206 bits
Modulation: 9-FSK, continuous phase
Channel bandwidth: 1.7361(1)Hz
Total occupied bandwidth: 15.625 Hz
Single tone duration: 0.576 sec
Information tones: 69
Synchronization: single channel, 16 tones

 

T10

Sequence time: 60s
Duration of transmission: 48.96 s
User information, per transmission: 72 bits
Code: convolutional, constraint length K=32, rate r=1/2, zero tail
Total bits sent per transmission: 206 bits
Modulation: 10-FSK, continuous phase
Channel occupied bandwidth: 1.7361(1) Hz
Channel spacings: 6.94(4) Hz
Total bandwidth: 62.5 Hz
Single tone duration: 0.576 sec
Information tones: 69
Synchronization: dual channel, 2x8 tones