

To test out Throb2000 V2.5
Unzip Throb25.zip into a suitable directory and run Throb25.exe from there.
Keep in a separate directory from previous Throb versions.
The program will start in the 2 Throb/sec speed.


Click on the setup menu command. Enter your callsign, this is vital for
the CW ident feature to work. The COM port keying facility may be entered
here but it may need re-entering each time you run, I am working on this.

Feed in audio as you would for PSK31 etc and observe that signals between
800 and 1100 Hz appear on the topmost waterfall. Avoid overloading which
will result in the waterfall display showing a red line.

Click  the Test On button and observe that a test signal appears on the
waterfall. Move the cursor on to the test signal and click on the very centre
of the signal. Note that the red signal band lines should now straddle the
signal exactly....this is crucial ( HINT, the test signal is at 900Hz). The
shape of the signal will be seen in the graphic window on the left side
below the waterfall and the red vertical bar shows where the sampling
of the signal starts. This is because the program starts with the
autosync facility switched on. You can switch the autosync off via the
button provided and then set the position of the red bar manually in the
left hand side of the by mouse clicking on the left half of the graphic
display. The test routine prints the whole character set, and will show
you what characters are available.

The small graphic window to the right shows the intensity of the decoded
tones in green. In operation, you should see one or two tones clearly when
receiving a reasonable signal. If you start to see more, look to the synch-
-ronisation and move the red vertical bar as above.


Note that two of the screens will be printing a message, only one of which
will make sense. This is to get over the USB/LSB problem. One screen decodes
the inverted signal and whether USB or LSB is being transmitted, one screen
should make sense.


Click the Test Off button.

Click the Tx On button. Now you should hear the transmit signal idling.
Type in something, which should appear in the right hand memo screen before
it is shifted out. Note the VERY slight changes in note as the signal is
encoded until the transmit buffer is empty and the idling tone (which is the
centre one of the nine) continues. This audio may be fed to an SSB TX in the
normal way. Note that two or three idling pulses are sent ahead of any data
thus allowing the receiving station to click on the single tone for accurate
tuning.

Running the test routine position the passband 1 or 2 Hz above or below
the 900Hz of the signal. Click on the AFC Button. Note that the AFC On label
appears and the passband will gradually centre the display on 900Hz. The
initial tuning must be within 3 Hz, the AFC will then hold the signal for a
drift of 1 hz in 5 secs or so.  The AFC may be switched off using the button
provided, but in practice this facility will always be needed.

Whilst in receive, the speed may be switched between 1,2 and 4 Throbs/sec.
1 Throb/sec is slow and for difficult circumstances. 2 Throbs/sec is for
a normal situation. 4 Throbs/sec is pushing the technique to the limit, and
is more suited to stronger signals say above S1.


History

23/5/2000 V1.1 Added AFC.
10/6/2000 V2.0 Complete rewrite.
               Altered to 1 or 2 tones out of 9 to allow coding in a single
               throb. 
               Speed increased to 12 wpm.
               simultaneous LSB/USB decoding.
13/6/2000 V2.1 Added Waterfall Sensitivity TrackBar.
               Added Help File.
21/6/2000 V2.2 Added 2 Throb/sec speed.
               Corrected bug which pevented 'W' printing on USB screen.
               Corrected bug which caused loss of keyboard characters
               on transmit.
11/7/2000 V2.3 Added 4 Throb/sec speed.
               Allowed change of speed without stopping program.
               Substituted apostrophe character for "="
               Added "@" character
23/7/2000 V2.4 Modified 4 Throb/sec speed for 144Hz bandwidth.
               Fixed loss of net frequency when changing speeds.
               Aligned CW Ident frequency to net frequency.
               CQ and QRZ facilities added.
               Made valid Memo screen enlargeable by clicking.
               Added 'shift' alphabet characters "=@?".
               Made idle character non printing (was space).
               Added a timed single tune up tone (on net frequency)
               Help file now .htm called by Explorer
               Center frequency of passband now marked
9/9/2000  V2.5 Removed "improvement" which had slightly reduced sensitivity
               Added delay facility to silence output for first throb to
               com port switched gear.
               Added further macros.
               Added facility to record transmitted text.
               Separated I/P and O/P functions of soundcard, so that program
               will now run on non-duplex soundcards.


