// Status=review
.Open a Wave File:

- Select *File | Open* and navigate to
+...\save\samples\130418_1742.wav+ under the _WSJT-X_ installation
directory.  When the file opens you should see something similar to
the to the following screen shot:

[[X12]]
image::images/r3556-main-ui-80.png[align="center",alt="Main UI and Wide Graph"]

.Decoding Overview

Notice the [green]*GREEN* and [red]*RED* markers on the waterfall
frequency scale.  Decoding takes place at the end of a receive
sequence and is organized in two stages.  The first decodes take place
at the selected Rx frequency, indicated by the [green]*GREEN* marker.
Results appear in both the left (*Band Activity*) and right (*Rx
Frequency*) text windows on the main screen. The program then finds
and decodes all signals in the selected mode or modes over the
displayed frequency range. The [red]*RED* marker indicates your Tx
frequency.

At least eight JT9 signals are present in the example file; all but
one of them are decodable.  When this file was recorded KF4RWA was
finishing a QSO with K1JT.  Since the green marker was placed at his
audio frequency, 1224 Hz, his message “K1JT KF4RWA 73” appears in the
*Rx Frequency* window. The *Band Activity* window shows this message
plus all the other decodes at nearby frequencies.  The CQ lines are
highlighted in [green]*GREEN*, and lines containing *My Call*, in this
case K1JT, are highlighted in [red]*RED*.

TIP: For this step and the next, you may want to pretend you are K1JT
by entering that callsign temporarily as *My Call* on the <<X11,*Setup
| Configuration*>> screen.  Your results should then be identical to
those shown in the screen shot above.

[[X13]]
.Decoding Controls

To gain some feeling for the controls frequently used when making
QSOs, try clicking with the mouse on the decoded text lines and on the
waterfall spectral display. You should be able to confirm the
following behavior:

- Double-click on either of the decoded lines highlighted in
green. This action produces the following results:

** Callsign and locator of a station calling CQ are copied to the *DX
Call* and *DX Grid* entry fields.

** Messages are generated for a minimal QSO.

** The *Tx even* box is checked or cleared appropriately, so that you
will transmit in the proper (odd or even) minutes.

** The Rx and Tx frequency markers are moved to the frequency of the
CQing station.

** The *Gen Msg* (``generated message'') radio button at bottom right 
of the main window is selected.

** If you have checked *Double-click on call sets Tx Enable* on the
*Setup* menu, *Enable Tx* is activated and a transmission starts
automatically at the appropriate time.

- Double-click on the decoded message ``K1JT N5KDV EM41'',
highlighted in [red]*RED*.  Results will be similar to those in the
previous step, except the Tx frequency ([red]*RED* marker) is not
moved.  Such messages are usually in response to your own CQ, or from
a tail-ender, and you probably want your Tx frequency to stay where it
was.

- By holding down the *Ctrl* key when double-clicking on the decoded line 
you can cause both Tx and Rx frequencies to be moved.  This behavior
can also be forced by checking *Lock Tx=Rx*. 

- Double-click on the message from KF4RWA in either window. He is
sending ``73'' to K1JT, signifying that the QSO is over.  Most likely
you want to send 73 to him, so the message ``KF4RWA K1JT 73'' is
automatically generated and selected for your next transmission.
(Alternatively, you might choose to send a free text message or to
call CQ again.)

- Click on the waterfall to set Rx frequency ([green]*GREEN* marker).

- Ctrl-click on waterfall to set both Rx and Tx frequencies.

- Double-click on the waterfall to set Rx frequency and start a
narrow-band decode there. Decoded text appears in the right window
only.  

- Ctrl-double-click to set both Rx and Tx frequencies and decodes at
the new frequency.

- Click *Erase* to clear the right window. 

- Double-click *Erase* to clear both text windows.