Emission

    The present complete emission types:

       Type                                             Notes
       ----                                             -----
        A2      Amplitude Modulated telegraphy          #1,2
        A3      DSB (full carrier telephony)
        A3A     SSB (reduced carrier telephony)
        A3B         (2 independent sidebands -
                     reduced carrier)                   #3
        A3J     SSB (supressed carrier telephony)
        A4      DSB facsimile
        A4A     SSB facsimile, reduced carrier
        A4J     SSB facsimile, supressed carrier
        A5      DSB television
        A5C     VSB television                          #4

        (Frequency modulation)

        F0      carrier - no modulation
        F1      frequency shift telegraphy              #1
        F2      frequency modulated telegraphy          #1,2
        F3      telephony
        F4      facsimile
        F5      television

        ---------------------Notes--------------------------

 1. This is not restricted to Morse - may be RTTY, for example.
    (RTTY  could  be  run  on 160 meters if on-off keying of
    the carrier is used).

 2. Examples of this mode  are:  1)  Carrier  keyed  on/off
    2) carrier  on  with the modulation keyed on/off  3)
    carrier on with the modulation frequency shift keyed.

 3. This is used by  short  wave  broadcast  station  studio to
    transmitter  links  with  separate  programs  on each set
    of sidebands.

 4. VSB = Vestigial sideband where all of one set  of side-
    bands is transmitted but only about 20 percent of the other
    set of sidebands is transmitted (the lowest frequencies).

    Common Amateur emissions:

    Double sideband voice = 6A3
    Single sideband voice = 3A3J
    VHF FM voice          = 16F3
    25 wpm Morse cw       = .1A1

    (assume max modulating freq of 3KHz and max deviation of
     5KHz)

     Bandwidths are found with the following formulae:

    A1  Bw = BK         K=5 for fading circuits)
    A2  Bw = BK+2M
    A3  Bw = 2M
    A3J Bw = M
    A4  Bw = KN+2M      (K=1.5)
    F1  Bw = 2.6D+.55B  (when 2D/B is less than 5.5)
        Bw = 2.1D+1.9B  (when 2D/B is greater than 5.5)
    F3  Bw = 2M+2DK     (K=1)
    F4  Bw = KN+2M+2D   (K=1.5)

                WHERE:

        Bw = necessary bandwidth in Hz
        B  = speed in bauds
        C  = subcarrier freq. in Hz
        D  = 1/2 the diff. between max and min instantaneous
                freq (in other words, peak deviation).
        K  = fudge factor
        M  = maximum modulating freq. in Hz
        N  = maximum black & white elements per second
                (N = drum circumference x lines per unit length
                    x drum rps)

As a result of WARC 79, the very familiar symbols of the
emissions modes will be changed.  The FCC will be implementing
the following new symbols over the next several years.

Old Symbol      New Symbol           Old Symbol      New Symbol

   A0              N0N                     F0              N0N
   A1              A1A                     F1              F1B
   A2              A2A                     F2              F2A
                   A2D                                     F2D
   A2J             J2A                     F3              F3E
                   J2D                     F4              F3C
   A3              A3E                     F5              F3F
   A3J             J3E                     P               P1B
   A4              A3C
   A5              C3F
                   A3F


Symbol Explanation:
  First character indicates emission type
  Second character indicates the nature of the signal
  Third character indicates the type of information transmitted

First Character
  N = Unmodulated carrier
  A = Double sideband AM
  J = Single sideband, suppressed carrier
  F = Frequency modulation
  P = Sequence of unmodulated pulses
  C = Vestigial sidebands

Second Character
  0 = No modulating signal
  1 = Single channel containing digital information without the
       use of a modulating subcarrier
  2 = Same as above, except using a modulating subcarrier
  3 = Single channel containing analog information

Third Character
  N = No information transmitted
  A = Telegraphy -- aural reception
  B = Telegraphy -- automatic reception
  C = Facsimile
  D = Data transmission, telemetry, telecommand
  E = Telephony
  F = Television

Example:  A1A is double sideband, single channel containing
          digital information without the use of a modulating
          subcarrier, telegraphy for aural reception.  In other
          words, CW!

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