// Status=review
The following buttons appear just under the decoded text windows on
the main screen:

//.Main UI Controls
image::images/main-ui-controls.png[align="left",alt="Main UI Controls"]

* *Log QSO* raises a dialog window pre-filled with known information
about a QSO you have nearly completed.  You can edit or add to this
information before clicking *OK* to log the QSO.  If you check *Prompt
me to log QSO* on the *Setup* menu, the program will raise the
confirmation screen automatically when you send a 73 or free-text
message.

//.Log QSO Window
image::images/log-qso.png[align="center",alt="Log QSO"]

* *Stop* will terminate normal data acquisition in case you want to
freeze the waterfall or open and explore a previously recorded audio
file.

* *Monitor* restarts normal receive operation.  This button is
highlighted in green when the _WSJT-X_ is receiving.

* *Erase* clears the right-hand decoded text window. 
Double-clicking *Erase* clears both text windows.

* *Decode* tells the program to repeat the decoding procedure at the
Rx frequency ([green]*GREEN* marker on waterfall), using the most recently
completed sequence of received data.  

* *Enable Tx* toggles the program into automatic T/R sequencing mode
and highlights the button in [red]*RED*.  A transmission will start at
the beginning of the selected (odd or even) sequence, or immediately
if appropriate.  A transmission will not be started any later than 24
s into a UTC minute.

* *Halt Tx* terminates a transmission in progress and disables
automatic T/R sequencing.

* *Tune* may be used to switch into Tx mode and generate an
unmodulated carrier at the specified Tx frequency ([red]*RED* marker
on waterfall).  This process may be useful for adjusting an antenna
tuner.  The button is highlighted in [red]*RED* while *Tune* is
active.  Toggle the button a second time to terminate the *Tune*
process.