WSJT-X/doc/user_guide/tutorial-example2.adoc

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// Status=review
.Wide Graph Settings:
- Set *Bins/Pixel* = 7
- Adjust the width of the Wide Graph window so that the upper
frequency limit is approximately 4000 Hz.
.Main Window:
- Select *JT9+JT65* on the *Mode* menu.
- Toggle the *Tx mode* button to read *Tx JT65*, and set the Tx and Rx
frequencies to 1718 Hz.
- Double-click on *Erase* to clear both text windows.
.Open a Wave File:
- Select *File | Open* and navigate to +...\save\samples\130610_2343.wav+.
The waterfall should look like this:
//.130610_2343.wav Decode
[[X14]]
image::images/130610_2343-wav-80.png[align="left",alt="Wide Graph Decode 130610_2343"]
IMPORTANT: Notice the [blue]*BLUE* marker on the waterfall scale, here
set at 2500 Hz. Its position is set by the spinner control *JT65 nnnn
JT9*, where nnnn is a frequency in Hz. In *JT9+JT65* mode the program
will automatically decode JT9 signals only above this frequency.
JT9 signals appear in the *Cumulative* spectrum as nearly rectangular
shapes about 16 Hz wide. They have no clearly visible sync tone like
the one at the low-frequency edge of all JT65 signals. By convention
the nominal frequency of both JT9 and JT65 signals is taken to be that
of the lowest tone, at the left edge of its spectrum.
This sample file contains 17 decodable signals — nine in JT65 mode
(flagged with the character # in the decoded text windows), and eight
in JT9 mode (flagged with @). On multi-core computers the decoders
for JT9 and JT65 modes run simultaneously, so their results will be
interspersed. The *Band Activity* window contains all decodes (you
might need to scroll back in the window to see some of them). A
signal at the frequency specified by the green marker is given
decoding priority, and its message is displayed in the *Rx Frequency*
window.
[[FigDecodes]]
image::images/decodes.png[align="center"]
- Confirm that mouse-click behavior is similar to that described
earlier, in <<TUT_EX1,Example 1>>. _WSJT-X_ automatically determines
the mode of each JT9 or JT65 message.
IMPORTANT: When you double-click on a signal in the waterfall it will be
properly decoded even if on the ``wrong'' side of the *JT65 nnnn JT9*
marker. The Tx mode automatically switches to that of the decoded
signal and the Rx and Tx frequency markers on the waterfall scale
resize themselves accordingly. When selecting a JT65 signal, click on
the sync tone at its left edge.
- Double-click on the waterfall near 815 Hz: a JT65 message
originating from W7VP will be decoded and appear in the *Rx Frequency*
window. Between the *UTC* and *Freq* columns on the decoded text line
you will find *dB*, the measured signal-to-noise ratio, and *DT*, the
signal's time offset in seconds relative to your computer clock.
[width="70%",cols="3,^3,^3,^4,^4,30",options="header"]
|=================================
|UTC|dB|DT|Freq|Mode|Message
|+2343+|+-7+|+0.3+|+815+|+#+|+KK4DSD W7VP -16+
|=================================
- Double-click on the waterfall at 3196 Hz. The program will decode a
JT9 message from IZ0MIT:
[width="70%",cols="3,^3,^3,^4,^4,30",options="header"]
|=====================================
|UTC|dB|DT|Freq|Mode|Message
|+2343+|+-7+|+0.3+|+3196+|+@+|+WB8QPG IZ0MIT -11+
|=====================================
- Scroll back in the *Band Activity* window and double-click on the
message +CQ DL7ACA JO40+. The program will set *Tx mode* to JT65 and Tx
and Rx frequencies to that of DL7ACA, 975 Hz. If you had checked
*Double-click on call sets Tx Enable* on the *Setup* menu, the program
would configure itself to start a QSO with DL7ACA.
- Double-click on the decoded JT65 message +CQ TA4A KM37+. The program
will set Tx mode to JT9 and the Rx and Tx frequencies to 3567 Hz. The
program is now configured properly for a JT9 QSO with TA4A.
.Reopen the First Sample File:
- Select *File | Open* and navigate to +...\save\samples\130418_1742.wav+.
Taking full advantage of the wide-band, dual-mode capability of
_WSJT-X_ requires a receiver bandwidth of at least 4 kHz. These
data were recorded with a much narrower Rx bandwidth, roughly 200 to
2400 Hz. If you have no Rx filter wider than about 2.7 kHz, you will
be using data like this. For best viewing, adjust *Bins/Pixel* and the
width of the Wide Graph so that only the active part of the spectrum
shows, say 200 to 2400 Hz. Re-open the example file after any change of
*Bins/Pixel* or Wide Graph width, to refresh the waterfall.
The signals in this file are all JT9 signals. To decode them
automatically in *JT9+JT65* mode youll need to move the *JT65 nnnn JT9*
delimiter down to 1000 Hz or less.
.Start, Zero, and Gain
Now is a good time to experiment with the *Start*, *Zero*, and *Gain*
parameters. *Start* determines the frequency displayed at the left
side of the waterfall scale. *Zero* sets the baseline level for
colors, and *Gain* sets the sensitivity for color changes. For the
receiver setup of this file good values are close to *Zero*=0,
*Gain*=0. You may want to uncheck *Flatten* when adjusting the *Zero*
and *Gain* controls. Re-open the wave file after each change, to see
the new results.
IMPORTANT: When finished with this Tutorial, dont forget to re-enter
your own callsign as *My Call* on the *Settings | General* tab.