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+<refentry id="FE_SET_VOLTAGE">
+  <refmeta>
+    <refentrytitle>ioctl FE_SET_VOLTAGE</refentrytitle>
+    &manvol;
+  </refmeta>
+
+  <refnamediv>
+    <refname>FE_SET_VOLTAGE</refname>
+    <refpurpose>Allow setting the DC level sent to the antenna subsystem.</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <funcsynopsis>
+      <funcprototype>
+	<funcdef>int <function>ioctl</function></funcdef>
+	<paramdef>int <parameter>fd</parameter></paramdef>
+	<paramdef>int <parameter>request</parameter></paramdef>
+	<paramdef>enum fe_sec_voltage *<parameter>voltage</parameter></paramdef>
+      </funcprototype>
+    </funcsynopsis>
+  </refsynopsisdiv>
+
+  <refsect1>
+    <title>Arguments</title>
+        <variablelist>
+      <varlistentry>
+	<term><parameter>fd</parameter></term>
+	<listitem>
+	  <para>&fe_fd;</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>request</parameter></term>
+	<listitem>
+	  <para>FE_SET_VOLTAGE</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>voltage</parameter></term>
+	<listitem>
+	  <para>pointer to &fe-sec-voltage;</para>
+	  <para>Valid values are described at &fe-sec-voltage;.</para>
+	</listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+    <title>Description</title>
+
+<para>This ioctl allows to set the DC voltage level sent through the antenna
+    cable to 13V, 18V or off.</para>
+<para>Usually, a satellite antenna subsystems require that the digital TV
+    device to send a DC voltage to feed power to the LNBf. Depending on the
+    LNBf type, the polarization or the intermediate frequency (IF) of the LNBf
+    can controlled by the voltage level. Other devices (for example, the ones
+    that implement DISEqC and multipoint LNBf's don't need to control the
+    voltage level, provided that either 13V or 18V is sent to power up the
+    LNBf.</para>
+<para>NOTE: if more than one device is connected to the same antenna,
+    setting a voltage level may interfere on other devices, as they may lose
+    the capability of setting polarization or IF. So, on those
+    cases, setting the voltage to SEC_VOLTAGE_OFF while the device is not is
+    used is recommended.</para>
+
+&return-value-dvb;
+</refsect1>
+
+</refentry>