47 CFR § 80.290
Auxiliary receiving antenna
February 16, 2021
An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available because a radio direction finder on board the vessel is operated.
[51 FR 31213, Sept. 2, 1986. Redesignated at 68 FR 46973, Aug. 7, 2003]