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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _FE_SET_VOLTAGE:
+
+********************
+ioctl FE_SET_VOLTAGE
+********************
+
+Name
+====
+
+FE_SET_VOLTAGE - Allow setting the DC level sent to the antenna subsystem.
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, FE_SET_VOLTAGE, enum fe_sec_voltage voltage )
+    :name: FE_SET_VOLTAGE
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <frontend_f_open>`.
+
+``voltage``
+    an integer enumered value described at :c:type:`fe_sec_voltage`
+
+
+Description
+===========
+
+This ioctl allows to set the DC voltage level sent through the antenna
+cable to 13V, 18V or off.
+
+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.
+
+.. attention:: 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.
+
+
+Return Value
+============
+
+On success 0 is returned.
+
+On error -1 is returned, and the ``errno`` variable is set
+appropriately.
+
+Generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.