We know you talk to yourself on the repeater.
A repeater is an automated radio station - usually mounted on a hilltop, tower, or tall building - that receives your signal on one frequency and simultaneously retransmits it on another. Repeaters solve the fundamental limitation of two-way radio: line-of-sight range.
UHF radio signals (where GMRS operates) travel in roughly straight lines. They don't bend around hills, mountains, or buildings. Two handhelds on flat ground might reach 1-3 miles. Put a building or ridge between them and that range drops to nearly zero. A mobile radio with more power helps, but terrain is still the limiting factor.
A repeater sits at an elevated location with a clear view of a large area. When you transmit, your signal reaches the repeater even if it can't reach the person you're talking to directly. The repeater then retransmits your signal from its elevated position, covering a much wider area.
Key concept: A repeater uses two frequencies - an input (where it listens for your signal) and an output (where it retransmits). On GMRS, the input is always 5 MHz above the output. Your radio handles this split automatically when programmed with the correct offset.
GMRS repeaters use channels 15R through 22R. Each channel has a pair of frequencies separated by 5 MHz. For example, channel 15R outputs on 462.5500 MHz and takes input on 467.5500 MHz. When you program a repeater into your radio, you set the output frequency and a +5 MHz transmit offset. Your radio then automatically transmits 5 MHz higher than what you're listening to. See Repeater Offsets for the full channel pair table.
Most repeaters require a CTCSS (PL) tone or DCS code to activate. This prevents the repeater from being triggered by stray signals or interference. You'll need to program the correct tone into your radio - without it, the repeater hears you but won't retransmit. Check repeater directories for the required tone. If you can hear a repeater but can't access it, see troubleshooting repeater access.
Elevation is everything. A repeater on a 1,000-foot hill with a good antenna can cover a 30-50 mile radius. The same repeater at ground level might only cover a few miles. This is why repeater operators spend significant effort finding the best possible locations - and why access to a good repeater is the single biggest range improvement you can make with GMRS.
Elevation is the biggest factor, but not the only one. A high-gain directional antenna can extend range in a specific direction. Surrounding terrain - ridges, valleys, dense urban development - creates shadow zones where signals don't reach. Two repeaters at the same height can have very different coverage footprints depending on what's around them. When you find that a repeater works great in one part of town but drops out entirely somewhere else, terrain is usually the reason.
A typical repeater installation is more than just a radio. The core components:
Putting this together and getting it to a remote hilltop site takes real effort and money. A basic repeater setup runs $500-$2,000 or more before you factor in site fees, coax, and installation.
Not every repeater is available to anyone who keys up:
Repeater listings on this site include access information where known. When in doubt, listen first and ask before transmitting.
A repeater is a shared resource. A few basics that keep things smooth:
Some repeaters are connected to other repeaters via RF links, extending coverage across a region. When you key up on one machine, your audio is simultaneously retransmitted on every linked site. Note that internet-based linking (EchoLink, AllStar, IRLP) is prohibited on GMRS per 95.1733(a)(8), but RF linking (radio-to-radio on GMRS frequencies) is permitted. See Repeater Linking on GMRS for the full regulatory picture.
Every repeater you use was built, installed, licensed, and maintained by someone - usually a hobbyist spending their own money and free time. Site rental, electricity, equipment repairs, and FCC coordination add up. If there's a local club or trustee behind a repeater you rely on, consider joining the club, making a donation, or simply saying thanks on the air. Repeaters don't maintain themselves.
Now that you understand the concept, learn how to actually use one: Using Repeaters covers programming, etiquette, and best practices for repeater operation.