47 C.F.R. § 95.371
In general, Personal Radio Services stations may transmit any emission type that is appropriate for the permissible uses of the specific service, provided that it does not exceed the authorized bandwidth for that service and is in full compliance with the modulation limits (if any) and unwanted emission limits for the specific service.
(b) Emission type designators. Emission type designators are defined in § 2.201 of this chapter. Designators for emissions commonly used in the Personal Radio Services are as follows:
| Description | Designator |
|---|---|
| Voice, AM | A3E |
| Voice, SSB | J3E |
| Voice, FM | F3E |
| Voice, PM | G3E |
| Data, FSK | F1D |
| Data, AFSK | F2D |
| Data, PSK | G1D |
| Test, no modulation | N0N |