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How to Find a Channel for a Radio Repeater

Radios using Citizen's Band, Family Radio Service or General Mobile Radio Service operate on a fixed-channel mode, so operators merely pick a specific numbered channel and use it. Whether the channel has an associated repeater cannot be easily determined by the operator, although organizations that use GRMS frequencies may inform authorized users of which frequencies are on a repeater network and which are "working" -- i.e., intended for short-range, non-repeated use between individual receivers. Amateur radio operators, however, can select specific frequencies. For a ham, identifying a repeater frequency involves both detective work and patience.

Instructions

- 1
  Isolate a specific frequency you believe might be controlled by a repeater. Most ham repeaters transmit periodic automated bulletins that announce the station identification and usually the date, time and any brief service notices from the licensee managing the repeater. These bulletins may appear at brief, regular intervals or only at the top or bottom of the hour.
- 2
  Use a local calling frequency -- e.g., 446.000 MHz or 146.520 MHz -- to ask a local ham about public or private repeaters open on a specific band plan. Some repeaters, especially those managed by a private radio club, require a specific squelch code -- known as the Continuous Tone-Coded Squelch System -- that overlays a sub-audible tone to a voice transmission that tells the repeater that the transmission is authorized for rebroadcast.
- 3
  Monitor the FM-input frequencies in a given band plan for any traffic. For example, the 2-meter band's preferred input channels range from 144.600 MHz to 144.900 MHz, and 146.010 MHz to 146.370 MHz.
- 4
  Contact the local area representative for the American Radio Relay League or a group like SkyWarn or the Amateur Radio Emergency Service to identify publicly sponsored repeaters that may be used for emergencies.

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