An important concept in the rules governing amateur radio is the concept of station control and the control operator. The control operator is the licensed radio amateur who is responsible for the transmissions of a station, and the location of that operator is called the control point. There are three ways that a control operator can control a station: local control, remote control, or automatic control.
Local control means direct manipulation of the transmitter by a control operator. (E1C07) So, when you were sitting in front of your radio, you are using local control.
A remotely controlled station is a station controlled indirectly through a control link. (E1C01) A control operator must be present at the control point is the true statement about remotely controlled amateur stations. (E1C06) This is, of course, true for local control as well. 3 minutes is the maximum permissible duration of a remotely controlled station’s transmissions if its control link malfunctions. (E1C08)
Automatic control of a station means the use of devices and procedures for control so that the control operator does not have to be present at a control point. (E1C02) The control operator responsibilities of a station under automatic control differs from one under local control. Under automatic control the control operator is not required to be present at the control point. (E1C03)
Most repeaters are operated with automatic control. Only auxiliary, repeater or space stations are the types of amateur stations that may automatically retransmit the radio signals of other amateur stations. (E1C10) 29.500 – 29.700 MHz is the frequency band available for an automatically-controlled repeater operating below 30 MHz. (E1C09) No repeaters are allowed on any other HF band.
An automatically controlled station may retransmit third party communications only when transmitting RTTY or data emissions. (E1C04) An automatically controlled station may never originate third party communications. (E1C05)