Hi Jim, I believe you will not find a reference to the language "modulating a single sideband transmitter" in the ITU or the FCC emission designator tables. That is language that was made up by someone else, and a common misconception. Just because there are references in ITU or NTIA or FCC language refering to digital signals J emission type, it does not confine all our digital emissions to J type.
For example, it matters not whether you use an SSB transmitter to generate an FSK signal. It is still emission type F. The emission designator table is silent on the "type of transmitter" that generates the signal. Whether it is an SSB balanced modulator, an I/Q system, a varactor oscillator, an LC oscillator, plate modulated AM, or a Direct-Digitally-Synthesized waveform, it simply does not matter to the emission designator how the signal is generated. It is not FCC's intention to regulate this. Here is the wording of the emission designator rule: "(1)First symbol--type of modulation of the main carrier; (2)Second symbol--nature of signal(s) modulating the main carrier; (3)Third symbol--type of information to be transmitted. " If you are receiving a signal, it may be impossible to tell how it is generated or what type of transmitter is being used. However, the signal may still be classified under an emission designator without knowledge of the transmitter technique. When viewed from this perspective, you will most likely arrive at the best emission designator for generic purposes. Some signals are combinations of emission types. These are the most difficult to categorize. Keep in mind that for different purposes, the same signal waveform may have different emission designators. That is because some of the emission designator definitions overlap or are redundant. There are also technical objectives for using certain emission designators over others. But, the FCC has not confined certain emission types to only be certain emission designators in its amateur rules. FCC has never said that all emissions from a computer soundcard feeding the balanced modulator input of an SSB transmitter must be defined as J2D emission types. In fact, for RTTY they continue to call it F1B whether you send it by soundcard or by DC shifting a reactance diode on the crystal of a class C transmitter. 73---Bonnie KQ6XA --- In [email protected], "jgorman01" <[EMAIL PROTECTED]> wrote: > > Bonnie, > > You need to revise your list somewhat, and everyone should know these > are not necessarily "official". The ITU (more specifically Working > Party 8A) shows Pactor II as 375HJ2D and Pactor III as 2K20J2D. I > would assume these are as official as it gets. > > In order for an emission to be classed as "G" it must be an > > Emission in which the main carrier is angle-modulated: > > Phase Modulation G > > There is no "main carrier" in a SSB transmitter because by > definition it is suppressed. > > It seems most folks look at the following definition as the correct one. > > Emission in which the main carrier is amplitude-modulated > (including cases where sub-carriers are angle-modulated): > Single-sideband, suppressed carrier J > > You'll notice this says specifically - "including cases where > sub-carriers are angle-modulated". > > Also MFSK16 is defined by the ITU as either 316HJ2D or 316HJ2B, > presumably based upon data or keyboarding. > > These are all from a letter that the NTIA has on its web site. > > Jim > WA0LYK >
