Who is accountable should a repeater inadvertently retransmit communications that violate the FCC rules?

The control operator of the repeater is responsible for ensuring that the repeater functions in compliance with FCC rules. If a repeater inadvertently retransmits communications that violate these rules, the accountability falls on the control operator of the repeater, as this individual is responsible for the operation and control of that station.

The control operator's role involves overseeing all transmissions from the repeater, and thus they must ensure that any communications being retransmitted adhere to legal and regulatory standards set by the FCC. This means that if there is a violation during a transmission, it is the control operator's responsibility to address it.

While the originating station and its control operator also share responsibility for their own transmissions, in this context, once the communication is picked up by the repeater, it is the determination and actions of the repeater’s control operator that come into play regarding compliance.

The owner of the repeater may also have a duty to ensure that their equipment meets regulatory requirements, but immediate accountability regarding the transmission lies with the control operator who has the ability to intervene at that moment. Thus, the correct answer focuses solely on the responsibility of the control operator in this scenario.