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Digital channel table

The digital channel table defines all digital DMR channels. As digital channels have some different options compared to analog channels, they are not defined within the same table. However, they share the same IDs. So be careful not to assign the same identifier to analog and digital channels.

The digital channel table has the form

Digital Name             Receive   Transmit  Power Scan TOT RO Admit  CC TS RxGL TxC GPS Roam ID
11      "DM0TT Ref"      439.0870  -7.6000   High  1    -   -  Free   1  1  7    12  -   +    -  
12      "DM0TT BB"       439.0875  -7.6000   High  -    -   -  Free   1  2  7    15  1   +    -  
84      "DMR_S0"         433.4500  433.4500  High  2    -   -  Free   1  1  6    9   -   +    -  
85      "DMR_S1"         433.6120  433.6120  High  2    -   -  Free   1  1  6    9   -   +    -  
86      "DMR_S2"         433.6250  433.6250  High  2    -   -  Free   1  1  6    9   -   +    -  
87      "DMR_S3"         433.6380  433.6380  High  2    -   -  Free   1  1  6    9   -   +    -  
88      "DMR_S4"         433.6500  433.6500  High  2    -   -  Free   1  1  6    9   -   +    -  
89      "DMR_S5"         433.6630  433.6630  High  2    -   -  Free   1  1  6    9   -   +    -  
90      "DMR_S6"         433.6750  433.6750  High  2    -   -  Free   1  1  6    9   -   +    -  
91      "DMR_S7"         433.6880  433.6880  High  2    -   -  Free   1  1  6    9   -   +    -  

The digital-channel table starts with the keyword "Digital" and ends with an empty line. The next keywords (Name, Receive, Transmit, Power, Scan, TOT, RO, Admit, CC, TS, RxGL and TxC, GPS, Roam, ID) are ignored and are maintained for the self-documentation of the configuration file.

Each channel is defined within a single line. The first column is the unique channel identifier (any unique number among analog AND digital channels). The second column specifies the channel name as a string. The third column specifies the RX frequency in MHz and the fourth column the TX frequency in MHz. Alternatively, a TX frequency can also be specified in terms of an offset relative to the RX frequency. In this case, the offset must be prefixed with either "+" or "-". The 5th (Power) column specifies the power level to use. Here, either the "High" or "Low" keyword must be used. The 6th (Scan) column specifies the ID of the scan-list (see below) attached to the channel. This list will be used whenever a scan is started on this channel. The 7th column (TOT) column specifies the TX time-out-timer in seconds or "-", if disabled. The 8th column (RO) specifies whether the channel is RX only ("+") or not ("-"). If enabled, you cannot transmit on that particular channel. The 9th (Admit) colum specifies the TX admit criterion for the channel. This must be either "-" or one of the keywords "Free" and "Color". "-" indicates that there is no restriction in transmitting on that channel. The radio will transmit whenever PTT is pressed. The "Free" keyword indicates that the radio will only transmit if the channel is free. The "Color" keyword indicates that the radio will only transmit if the channel is free and the color-code of the repeater matches the specified color-code of the channel (see next column). The 10th column specifies the color-code of the channel. The 10th (CC) column specifies the color-code of the channel. To avoid interference between neighboring radios and repeaters on the same frequency (in case of DX conditions), the repeater and radio will only react to transmissions on a channel with the matching color-code. The color-code can be any number between 0 and 15. The 11th (TS) column specifies the time-slot for this channel. Due to the audio compression used in DMR, it is possible to operate two independent channels on a single frequency by using time-slicing. DMR uses two time-slots. This option specifies which of the two time-slots is used for the channel. On simplex channels, this time-slicing is irrelevant, as there is no central instance (the repeater) that defines what time-slot 1 or 2 is. The 12th (GPS) column specifies the GPS or APRS system (see below) to use on that channel. The 13th (Roam) column specifies the roaming zone. This can either be '-' meaning roaming disabled or an ID of a roaming zone specified below. Finally, the 14th column (ID) specifies the DMR ID to use with this channel. That is either '-' for default ID or an index (0-based) of the ID list above.