What type of amateur station simultaneously retransmits the signal of another amateur station on a different channel or channels?

A repeater station is specifically designed to receive a signal on one frequency and retransmit it on a different frequency. This functionality is crucial in amateur radio as it enables communication over longer distances or in areas where direct line-of-sight contact is challenging. By retransmitting the signal on a different channel, repeaters effectively increase the range of an amateur radio signal, allowing more operators to communicate beyond the limitations of their individual transmitters.

It's important to note that beacons, earth stations, and message forwarding stations serve different purposes. A beacon station transmits a continuous signal to indicate its presence or location, an earth station is typically involved in satellite communications, and a message forwarding station relates to the relay of messages rather than direct signal retransmission like a repeater. This distinction reinforces why the concept of a repeater station is essential for enhancing communication capabilities in the amateur radio realm.