What is a repeater ?

Repeaters are to be found across the country, mainly on bands between 50MHz and 23cm. A repeater is an un-manned station that will re-transmit any signal heard on its input frequency on its output frequency, subject to access conditions such as a tone burst, or tone squelch. Repeaters are most commonly found on 2 metres (144 - 146 MHz) and 70 cm (432 - 440MHz). The signal heard on the input of the repeater is re-transmitted on a different frequency to avoid interference. This is known as the repeater shift. This is most commonly -600kHz for 2 metres, and +1.6MHz for 70cms.

Repeaters cost money to run and are paid for by local groups and clubs. If you regularly use a repeater, ask the repeater group how you can join.

How do I use a repeater ?

With your transceiver, set the displayed frequency to the output frequency of the repeater you wish to use. Locate the button or function on the transceiver to enable repeater mode, or set the repeater shift, where there is an option for either positive or negative transmit shift then make sure that it is set to negative for the 2m band and positive for the 70cm band.

To use a repeater, key the PTT (push-to-talk), send a short burst of 1750Hz tone (most rigs have a tone burst facility), keep the PTT keyed and speak for a few seconds (but not during the tone-burst), release the PTT and you should receive a pip or some other indication that your signal was recognised by the repeater. The 1750Hz tone-burst is only needed when the repeater is not already in use. Some repeaters have the facility to accept CTCSS instead of a tone burst. If a transceiver and repeater are capable of using CTCSS then this should be used instead of a tone burst.

What is CTCSS (Tone Squelch) ?

CTCSS stands for Continuous Tone Coded Squelch System. The idea is that a sub audible tone is continuously transmitted in addition to the speech (or other) signal. The tones used are below the normal hearing frequency range. In the UK these tones may be used instead of the 1750Hz tone burst to access repeaters. The UK is divided into 23 areas and a particular tone has been allocated to each area. Those repeaters that support CTCSS will normally send the appropriate letter (designating the tone frequency) in morse after the repeater callsign.