+ <para><link linkend="sdr">SDR</link> specific tuner types are
+<constant>V4L2_TUNER_SDR</constant> and <constant>V4L2_TUNER_RF</constant>.
+For SDR devices <structfield>audmode</structfield> field must be
+initialized to zero.
+The term 'tuner' means SDR receiver in this context.</para>
+