mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-09-19 03:36:33 -04:00
784e246557
bad data. 2. Fix a bug that could allow a Koetter-Vardy false decode instead of a valid Berlekamp-Massey decode, sometimes leading to program crash. 3. Many more edits in the User's Guide, *.adoc files. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@3664 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
45 lines
2.1 KiB
Plaintext
45 lines
2.1 KiB
Plaintext
// Status=review
|
||
.Receiver Noise Level
|
||
|
||
- Click the *Monitor* button to return to normal receive operation
|
||
(button should be highlighted in [green]*GREEN*).
|
||
|
||
- Set your transceiver to USB (or USB Data) mode.
|
||
|
||
- 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.
|
||
|
||
.Bandwidth and Frequency Setting
|
||
|
||
Taking full advantage of the wide-band, dual-mode capability of
|
||
_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
|
||
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.
|
||
|
||
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
|
||
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.
|
||
|
||
IMPORTANT: When finished with this Tutorial, don’t forget to re-enter
|
||
your own call-sign as *My Call*.
|
||
|