What is meant by "repeater offset"?

"Repeater offset" refers to the difference between a repeater's transmit frequency and its receive frequency. In amateur radio, repeaters are used to extend the range of communication by receiving a signal on one frequency and then retransmitting it on another. The offset is typically necessary because it allows for the simultaneous transmission and reception of signals without causing interference to the users of the repeater.

For example, a common offset might be set at 600 kHz, meaning if the repeater is set to receive a signal on a frequency of 144.390 MHz, it would retransmit that signal on 144.990 MHz. This specific frequency separation is crucial in avoiding overlap with the incoming signal and allows multiple users to utilize the same repeater without disruptions in communication. The concept of a repeater offset is fundamental to understanding how repeaters operate in the amateur radio frequency spectrum.