47 CFR §80.97
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
This section applies to ships and coast stations authorized to transmit in the band 405-525 kHz.
- (a)Except for the transmission of distress or urgency signals, all transmissions must cease within the band 485-515 kHz during each 500 kHz silence period.
- (b)Stations transmitting telegraphy must use the service abbreviations (“Q” code) listed in Appendix 14 to the Radio Regulations.
- (c)The call consists of:
- (1)The call sign of the station called, not more than twice; the word “DE” and the call sign of the calling station, not more than twice; if useful, the frequency on which the called station should reply; and the letter “K”.
- (2)If the call is transmitted twice at an interval of not less than one minute, it must not be repeated until after an interval of three minutes.
- (d)The reply to calls consists of: The call sign of the calling station, not more than twice; the word “DE”; and the call sign of the station called, once only.