Repeater Access Tones

With so many more repeaters today on frequencies so close together, repeaters are controlled with sub-audible tones to limit access and reduce interference. The tone frequency or DCS code assigned to a repeater is generally published with other information. Sometimes that information is available from club members or from the repeater operator.

The sub-audible tones is sent to the repeater along with your transmission. You need only setup the function correctly on the radio. The radio takes it from there automatically when you key up.

Anywhere you see reference to CTCSS, the text is referring to a an analog tone frequency. DCS refers to a digital signal (however this is not the tone used in D-Star operations. That is handled through other settings in those radios). An analog repeater can use a digital tone.This is all configured by the repeater operator.

Your radio is configured for these tones through a two step process. The process in the programmer is similar to that of the radio: 1) turn on the Tone Mode; then 2) select the tone frequency (CTCSS) or DCS code.

NOTE: The value of the tone that the radio transmits and/or receives is selected from those available in one of four columns:

CTCSS - Analog tone frequencies

RX CTCSS - Analog tone frequencies received by the radio (where available - not all radios have the ability to use a separate transmit and receive tone value.)

DCS - Digital tone codes.

RX DCS - Digital tone codes for digital signals received by the radio (where available - not all radios have the ability to use a separate transmit and receive DCS value).

When radios do not have the ability to use separate CTCSS or DCS tones for transmission and reception, the one tone shown in the CTCSS or DCS column will be used for BOTH transmission and reception.

The Tone Modes include:

• None - No tone system activated. Even if the CTCSS, RX CTCSS. and DCS Code columns are set to a value, the radio will not open the repeater since the tone functionality is not engaged.
• Tone - CTCSS tone is transmitted only This mode is most common for amateur repeater operations. When this option is selected, the CTCSS column becomes available. Select the tone frequency from those in the list. The value must be in the list. The values that appear in the RX CTCSS, DCS and RX DCS columns are ignored by the radio when this option is being used.
  
  
• T Sql - CTCSS tone is transmitted AND the radio uses a CTCSS tone to block incoming signals. In this mode only signals with the same CTCSS tone will be heard by the radio. Your radio remains silent otherwise. When this option is selected the CTCSS column becomes available (in some radios the CTCSS and the RX CTCSS columns become available). Select the code from those in the list. The values must be in the list. Note: Be aware that many repeaters do not return tones with the output signal. If you can see activity as indicated by the signal strength meter on the face of the radio but you cannot hear anything even when you adjust volume and squelch on with the knobs on the radio, you probably have Tone Mode set to TSql when it should be set to Tone. Or, you have an incorrect CTCSS or RX CTCSS value set.
  
  
• DCS - A digital tone is transmitted AND the radio uses a digital code to block incoming signals. This mode is used in many commercial systems; however, some amateur repeaters have begun to use it also. When this option is selected, the DCS column becomes available (in some radios the DCS and the RX DCS columns become available.) Select the code from those in the list. The value must be in the list.
• D Code - A digital tone is transmitted ONLY. When this option is selected, the DCS column becomes available Select the code from those in the list. The value must be in the list.
• T DCS - A CTCSS tone is transmitted AND the radio uses a digital code to block incoming signals. When this option is selected, the CTCSS and DCS (or in some radios the RX DCS) columns become available. Select the code from those in the list. The value must be in the list.
  
  
• D Tone - A digital tone is transmitted AND the radio uses a CTCSS code to block incoming signals. When this option is selected, the DCS and CTCSS (or in some radios the RX CTCSS) columns become available. Select the code from those in the list. The value must be in the list.

Remember, if you are just listening, you don't need tones. Leave Tone Mode set to None on channels that you monitor.