Ahli TARS Beaufort

Ahli TARS Beaufort

HF

HF

Bandwidth

The bandwidth is expressed as three digits and a letter that occupies the position normally used for a decimal point. The letter indicates what unit of frequency is used to express the bandwidth. H indicates hertz, K indicates kilohertz, M indicates megahertz, and G indicates gigahertz. For instance, "500H" means 500 Hz, and "2M50" means 2.5 MHz.

Type of modulation
N Unmodulated carrier
A Double-sideband amplitude modulation (e.g. AM broadcast radio)
H Single-sideband with full carrier (e.g. as used by CHU)
R Single-sideband with reduced or variable carrier
J Single-sideband with suppressed carrier (e.g. Shortwave utility and amateur stations)
B Independent sideband (two sidebands containing different signals)
C Vestigial sideband (e.g. NTSC)
F Frequency modulation (e.g. FM broadcast radio)
G Phase modulation
D Combination of AM and FM or PM
P Sequence of pulses without modulation
K Pulse amplitude modulation
L Pulse width modulation (e.g. as used by WWVB)
M Pulse position modulation
Q Sequence of pulses, phase or frequency modulation within each pulse
V Combination of pulse modulation methods
W Combination of any of the above
X None of the above

Type of modulating signal
0 No modulating signal
1 One channel containing digital information, no subcarrier
2 One channel containing digital information, using a subcarrier
3 One channel containing analogue information
7 More than one channel containing digital information
8 More than one channel containing analogue information
9 Combination of analogue and digital channels
X None of the above

[Type of transmitted information
N No transmitted information
A Aural telegraphy, intended to be decoded by ear, such as Morse code
B Electronic telegraphy, intended to be decoded by machine (Radioteletype and digital modes)
C Facsimile (Still images)
D Telemetry or Telecommand (Remote control or data collection)
E Telephony (voice or music intended to be listened to by a human)
F Video (television signals)
W Combination of any of the above
X None of the above

Details of information
A Two-condition code, elements vary in quantity and duration
B Two-condition code, elements fixed in quantity and duration
C Two-condition code, elements fixed in quantity and duration, error-correction included
D Four-condition code, one condition per "signal element"
E Multi-condition code, one condition per "signal element"
F Multi-condition code, one character represented by one or more conditions
G Monophonic broadcast-quality sound
H Stereophonic or quadraphonic broadcast-quality sound
J Commercial-quality sound (non-broadcast)
K Commercial-quality sound—frequency inversion and-or "band-splitting" employed
L Commercial-quality sound, independent FM signals, such as pilot tones, used to control the demodulated signal
M Greyscale images or video
N Full-color images or video
W Combination of two or more of the above
X None of the above

Multiplexing
N None used
C Code-division (excluding spread spectrum)
F Frequency-division
T Time-division
W Combination of Frequency-division and Time-division
X None of the above

Common and important examples

N0N
Continuous, unmodulated carrier - as previously commonly used for radio direction finding (RDF) in marine and aeronautical navigation.
A1A
Signalling by keying the carrier directly (aka CW or OOK) - as currently used in amateur radio. This is often but not necessarily Morse code.
A2A
Signalling by keying a tone modulated onto a carrier so that it can easily be heard using an ordinary AM receiver - as previously used for station idents of some RDF transmissions. This is usually but not exclusively Morse code. (An example of modulated continuous wave)
A3E
AM speech communication - as used for aeronautical VHF communications
F3E
FM speech communication - as used for marine and many other VHF communications
J3E
SSB speech communication - as used on HF bands by marine, aeronautical and amateur users
A3E or A3EG
Normal AM broadcast - as found on public LF and MF bands
F1B
FSK telegraphy, such as RTTY. [1]
F2D
Data transmission by frequency modulation of a radio frequency carrier with an audio frequency FSK subcarrier. Often called AFSK/FM.
F8E or F8EH
Normal FM stereo broadcast - as found on public VHF band, and as the audio component of broadcast television transmissions
G1B
PSK31 (BPSK31)
C3F or C3FN
Broadcast television video signals

Note that there is some overlap, so a signal might legitimately be described by two or more designators. In such cases, there is often a traditionally preferred designator.

untuk info bersama. dalam soalan RAE biasanya akan keluar..
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