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<h1 style="text-align: center;">DominoEX - Operating</h1>
Fldigi can operate in the following DominoEX modes:<br>
<ul>
<li>dominoEX-4</li>
<li>dominoEX-5</li>
<li>dominoEX-8</li>
<li>dominoEX-11</li>
<li>dominoEX-16, and</li>
<li>dominoEX-22</li>
</ul>
The sound card sampling rate is 8000 Hz for the 4, 8 and 16 modes.
It is 11025 Hz for the 5, 11 and 22 modes. This change in
sound card sampling rate will be seen in the drop rate on the waterfall. See <a href="Modes/DominoEXdesc.htm">DominoEX Technical Description</a>.<br>
<br>
The modem code for dominoEX uses a wide band multiple frequency
detector that can lock on and detect the incoming signal even when
badly mistuned. Frequency domain oversampling is used to allow
proper tone detection with the need for AFC. The AFC control does
not alter the decoder in any way.<br><br>
The waterfall and digiscope will appear as:<br>
<br>
<div style="text-align: center;"><img style="width: 791px; height: 198px;" alt="" src="images/dominoex-1.jpg"><br>
<br>
<div style="text-align: left;">The text displayed in the status area is
the secondary text being sent by the transmitting station. When
the keyboard buffer is empty the dominoEX modem transmits text from the
secondary text buffer. Your secondary text buffer can be edited
on the DominoEX configuration tab.</div>
<br>
<div style="text-align: left;">The digiscope display represents the tone pairs moving through the tone filters.
You can also use an alternate digiscope display (left click on
the digiscope display area).<br>
<br>
<div style="text-align: center;"><img style="width: 117px; height: 117px;" alt="" src="images/dominoex-1a.png"><br>
<br>
<div style="text-align: left;">In this display mode the red line
represents the center of the multiple tone bins that are in the
detector. The dots will be blurry if the AFC is not locked on and
become very distinct when AFC lock has been achieved. The tone
dots will move from bottom to top (opposite the direction of the
waterfall).</div>
</div>
</div>
</div>
<br>
This is the same signal mistuned:<br>
<br>
<div style="text-align: center;"><img style="width: 871px; height: 115px;" alt="" src="images/dominoex-2.png"><br>
<div style="text-align: left;"><br>
and with the signal badly mistuned:<br>
<br>
<div style="text-align: center;"><img style="width: 871px; height: 117px;" alt="" src="images/dominoex-3.png"><br>
<br>
<div style="text-align: center;"><h4><a href="index.html">Contents</a></h4><a href="index.html"></a><br></div>
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