comdtinst m2400.1f - US Coast Guard Response Boat-Medium

1.J.4. Emissions Abbreviations. Necessary bandwidths are expressed
using a letter in lieu of a decimal to indicate the bandwidth of an
emission as follows:
(a) Hertz. .01 to 999.99 Hz in hertz using the letter H;
6H1 = 6.1 Hz
(b) Kilohertz. 1.00 to 999.99 kHz in kilohertz using the
letter K; 1K1 = 1.1 kHz
(c) Megahertz. 1.00 to 999.99 MHz in megahertz using
the letter M; 2M1 = 2.1 MHz
(d) Gigahertz. 1.00 to 999.99 GHz in gigahertz using the
letter G; 6G5 = 6.5 GHz
5. Emission Classification Symbol. Emission classification
symbols are derived from the tables below. A basic emission
designator consists of three symbols, and if desired, two optional
additional symbols.
(a) First symbol - designates the type of modulation of
the main carrier: (figure 1-1)
(b) Second symbol - designates the nature of signal(s)
modulating the main carrier: (figure 1-2)
(c) Third symbol - designates the type of information to
be transmitted. (In this context the word "information"
does not include information of a constant, unvarying
nature such as provided by standard frequency emissions,
continuous wave and pulse radars, etc.) (figure 1-3)
(d) Fourth symbol - designates the details of signal(s):
(figure 1-4)
(e) Fifth symbol - designates the nature of multiplexing:
(figure 1-5)
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