2014-01-23 15:12:12 -05:00
|
|
|
|
// Status=review
|
|
|
|
|
.Receiver Noise Level
|
2014-01-24 15:09:47 -05:00
|
|
|
|
|
|
|
|
|
- Click the *Monitor* button to return to normal receive operation
|
|
|
|
|
(button should be highlighted in [green]*GREEN*).
|
|
|
|
|
|
2014-01-23 15:12:12 -05:00
|
|
|
|
- Set your transceiver to USB (or USB Data) mode.
|
2014-01-24 15:09:47 -05:00
|
|
|
|
|
|
|
|
|
- Use the receiver gain controls and/or Windows mixer controls to set
|
|
|
|
|
the background noise level (scale at lower left of main window) to
|
|
|
|
|
around 30 dB with no signals present. If necessary you can also use
|
|
|
|
|
the slider next to the scale, but note that the overall dynamic range
|
|
|
|
|
will be best with this slider not too far from its mid-point.
|
2014-01-23 15:12:12 -05:00
|
|
|
|
|
|
|
|
|
.Bandwidth and Frequency Setting
|
|
|
|
|
|
|
|
|
|
Taking full advantage of the wide-band, dual-mode capability of
|
2014-01-24 15:09:47 -05:00
|
|
|
|
_WSJT-X_ requires a receiver bandwidth of at least 4 kHz. Many SSB
|
|
|
|
|
transceivers have a fixed-width Tx filter that will not pass audio
|
|
|
|
|
frequencies higher than about 2700 Hz. _WSJT-X_ takes care of this by
|
2014-01-27 16:28:54 -05:00
|
|
|
|
using *Split Tx* mode, receiving with *VFO A* and transmitting with
|
|
|
|
|
*VFO B*. Under CAT control _WSJT-X_ offsets the Tx dial frequency
|
|
|
|
|
(*VFO B*) in 500 Hz steps, adjusting the generated audio frequency so
|
|
|
|
|
that it always falls in the range 1500 – 2000 Hz. With *CAT* and
|
|
|
|
|
*Split Tx* enabled on the configuration screen and your transceiver
|
|
|
|
|
set to *Split* mode, this frequency control will be handled
|
|
|
|
|
automatically.
|
2014-01-23 15:12:12 -05:00
|
|
|
|
|
|
|
|
|
If your transceiver has only a standard SSB filter you won’t be able
|
|
|
|
|
to use more than about 2.7 kHz bandwidth. You can still have all of
|
2014-01-24 15:09:47 -05:00
|
|
|
|
the JT9 sub-band and part of the JT65 sub-band available on screen,
|
|
|
|
|
however. On 20m, say, set dial frequency (*VFO A*) to 14.0774 and the
|
|
|
|
|
*JT9 nnnn JT65* dividing line at 1600 Hz. JT9 signals in their
|
|
|
|
|
conventional sub-band will then appear at 1600 – 2600 Hz, while JT65
|
|
|
|
|
signals will be below 1000 Hz. Of course, you might prefer to
|
|
|
|
|
concentrate on one mode at a time, setting your dial frequency to
|
|
|
|
|
(say) 14.076 for JT65 and 14.078 for JT9. Present conventions have
|
|
|
|
|
the nominal JT9 dial frequency 2 kHz higher than the JT65 dial
|
|
|
|
|
frequency, and the checkbox labeled *+2 kHz*, just below the *Band*
|
|
|
|
|
selector, makes the appropriate settings easy.
|
2014-01-27 16:28:54 -05:00
|
|
|
|
|
|
|
|
|
IMPORTANT: When finished with this Tutorial, don’t forget to re-enter
|
|
|
|
|
your own call-sign as *My Call*.
|
|
|
|
|
|