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// Status=review
.Main Window:
- Click the *Stop* button on the main window to halt any data acquisition.
- Select *FT8* from the *Mode* menu and *Deep* from the *Decode* menu.
- Double-click on *Erase* to clear both text windows.
.Open a Wave File:
- Select *File | Open* and navigate to
+...\save\samples\FT8\210703_133430.wav+. The waterfall and *Band
Activity/Rx Frequency* windows should look something like the
following screen shots:
- You may want to pretend you are K1JT
by entering that callsign temporarily as *My Call* on the
*Settings | General* tab. Your results should then be identical to
those shown in the screen shot below. Don't forget to change *My Call*
back to your own call when you are done!
[[X15]]
image::ft8_decodes.png[align="left"]
.Decoding Overview
Decoding takes place at the end of a receive sequence. With *Decode* set
to *Deep*, three decoding passes will be done and the *Decode* button on the
main window will illuminate three times, once for each pass.
The first decoding attempt in each pass is done at the selected Rx frequency,
indicated by the U-shaped green marker on the waterfall frequency
scale. All decodes appear in the left (*Band Activity*) window. The right
(*Rx Frequency*) text window displays any decodes obtained at the current
Rx frequency along with any decodes addressed to *My Call* (K1JT in this case).
The red marker on the waterfall scale indicates your
Tx frequency.
Twenty-one FT8 signals are decoded from the example file. The number
of decodes is shown in a box at the bottom of the main window. When
this file was recorded HA5WA was finishing a QSO with K1JT, and his 73
message is shown in red because it is addressed to *My Call* (in this
case K1JT). By default, lines containing CQ are highlighted in green,
and lines with *My Call* (K1JT) in red. Notice that K1JT now has two
additional callers; HA0DU and EA3AGB.
[[X13]]
.Decoding Controls
To gain some feeling for controls frequently used when making QSOs,
try double-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 one of the decoded CQ messages highlighted in
green. These actions produce the following results:
** Callsign and locator of the station calling CQ are copied to the *DX
Call* and *DX Grid* entry fields.
** Messages are generated for a standard 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 frequency marker is moved to the frequency of the CQing
station.
** You can modify the double-click behavior by holding down the
*Shift* key to move only the Tx frequency or the *Ctrl* key to move
both Rx and Tx frequencies. (On a Mac computer, use the *Command* key
instead of *Ctrl*).
** In addition, if *Double-click on call sets Tx enable* is checked on the
*Settings | General* tab then *Enable Tx* will be activated
so that a transmission will start automatically at the proper time.
+
NOTE: You can prevent your Tx frequency from being changed by checking the
box *Hold Tx Freq*.
- Double-click on the decoded message `K1JT HA0DU KN07`, highlighted
in red. Results will be similar to those in the previous step. The Tx
frequency (red marker) is not moved unless *Shift* or *Ctrl* is held
down. Messages highlighted in red 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.
- Click with the mouse anywhere on the waterfall display. The green Rx
frequency marker will jump to your selected frequency, and the Rx
frequency control on the main window will be updated accordingly.
- Do the same thing with the *Shift* key held down. Now the red Tx
frequency marker and its associated control on the main window will
follow your frequency selections.
- Do the same thing with the *Ctrl* key held down. Now both colored
markers and both spinner controls will follow your selections.
- Double-clicking at any frequency on the waterfall does all the
things just described and also invokes the decoder in a small range
around the Rx frequency. To decode a particular signal, double-click
near the left edge of its waterfall trace.
- Ctrl-double-click on a signal to set both Rx and Tx frequencies and
decode at the new frequency.
- Click *Erase* to clear the right window.
- Double-click *Erase* to clear both text windows.
TIP: To avoid QRM from competing callers, it is usually best
to answer a CQ on a different frequency from that of the CQing
station. The same is true when you tail-end another QSO. Choose a Tx
frequency that appears to be not in use. You might want to check the
box *Hold Tx Freq*.
TIP: Keyboard shortcuts *Shift+F11* and *Shift+F12* provide an easy
way to move your Tx frequency down or up in 60 Hz steps.
TIP: Sliders and spinner controls respond to *Arrow* key presses
and *Page Up/Down* key presses, with the *Page* keys moving the
controls in larger steps. You can also type numbers directly into
the spinner controls or use the mouse wheel.
TIP: An online {ft8_tips} by ZL2IFB offers many additional tips on
operating procedures.
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