<?xml version="1.0" encoding="UTF-8"?>

<section xml:id="confAnalogChannels"
         xmlns="http://docbook.org/ns/docbook"
         xmlns:xlink="http://www.w3.org/1999/xlink">

<info>
  <title>Analog channel table</title>
</info>

<para>
  The analog channel table collects all analog (FM) 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.
</para>

<para>
  The analog channel table has the form
</para>

<informalexample pgwide="1">
  <programlisting><![CDATA[Analog  Name             Receive   Transmit Power Scan TOT RO Admit  Squelch RxTone TxTone Width APRS
1       "Y07"            144.6750  144.6750  High  1    -   -  Free   1       -      -     12.5  -
2       "S20"            145.3000  145.3000  High  -    -   -  Free   1       -      -     12.5  -
3       "Mobil 2m"       145.5000  145.5000  High  -    -   -  Free   1       -      -     12.5  2
4       "DB0RAG"         439.3000  -7.6000   High  1    -   -  Free   3       -      -     12.5  -
5       "DB0LOS"         438.7750  -7.6000   High  1    -   -  Free   1       -      -     12.5  -
6       "DB0LUD"         438.5750  -7.6000   High  1    -   -  Free   1       -      67    12.5  -
19      "DB0BLO"         439.2750  -7.6000   High  1    -   -  Free   3       -      -     12.5  -
20      "DB0SP-2"        145.6000  -0.6000   High  1    -   -  Free   3       -      -     12.5  -
21      "DB0SP-70"       439.4250  -7.6000   High  1    -   -  Free   3       -      -     12.5  -
]]></programlisting>
</informalexample>

<para>
  The analog channel table starts with the "Analog" keyword and ends with an empty line. The
  remaining keywords right after "Analog" (i.e., "Name", "Receive", "Transmit", "Power", "Scan",
  "TOT", "RO", "Admit", "Squelch", "RxTone", "TxTone" and "Width") are ignored but are part of the
  self-documentation of the config file.
</para>

<para>
  Each line within the table specifies a single channel. The first column specifies the unique ID
  of the channel. This ID can by any number that is unique among analog AND digital channels. The
  second (Name) column specifies the name of the channel as a string. Any string can be used here.
</para>
<para>
  The third (Receive) column specifies the RX frequency of the channel in MHz. The fourth
  (Transmit) column specifies the TX frequency in MHz or alternatively, an offset relative to the
  receive frequency in MHz by prefixing "+" or "-". 
</para>
<para>
  The 5th (Power) column specifies the transmit
  power. This must be either the "High" or "Low" keyword. The 6th (Scan) column specifies the
  scan-list ID for this channel or "-" if there is no scan-list assigned to the channel. A scan-list
  (see below) is just a collection of channels that gets scanned whenever scanning is started on a
  particular channel. 
</para>
<para>
  The 7th (TOT) column specifies the transmit time-out in seconds or "-" if
  disabled. The 8th (RO) column specifies whether this channel is receive-only with either "-"
  meaning disabled and "+" enabled. If enabled, it is impossible to transmit on that channel. 
</para>
<para>
  The 9th column specifies the admit criterion on that channel. This must be either "-" meaning that
  there is no restriction when to send on that channel, the keyword "Free" meaning that the channel
  must be free to transmit or the keyword "Tone" meaning that the channel must be free and the
  RxTone must match. 
</para>
<para>
  The 10th (Squelch) column specifies the squelch level for the channel. This
  must be a number between [0-10]. The larger the value, the stronger the signal must be to open
  the squelch. The value 0 disables the squelch. 
</para>
<para>
  The 11th (RxTone) specifies the receive CTCSS tone
  frequency in Hz. The squelch will then only open, if the signal is strong enough (see previous
  column) and the specified tone is received. If set "-" the RX tone is disabled and the squelch
  will open if the signal is strong enough. The 12th (TxTone) column specifies the CTCSS tone
  to transmit in Hz or "-" if disabled. This feature is used by some repeaters to open their
  squelch and to start repeating to avoid conflicts between repeaters operating on the same
  frequency (e.g., in case of DX conditions). 
</para>
<para>
  The 13th (Width) column specifies the
  bandwidth of the channel in kHz. This can be 12.5kHz narrow-band or 25kHz wide-band.
  Finally, the 14th column specifies the APRS system ID to use or "-" for <emphasis>APRS 
  disabled</emphasis>.
</para>

</section>
