dl-fldigi/fldigi_doxygen/user_src_docs/throb.txt

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/**
\page throb_page Throb
\tableofcontents
The THROB family of modes use two tones at a time. These tones are also
amplitude modulated and can be a single tone for some symbols.
<br>
The mode has no Forward Error Correction, and is difficult to
tune. It is fairly sensitive and moderately robust. Keyboard-to-keyboard QSOs
are reasonably fast.
<br>
Tuning must be very accurate, and the software will not tolerate
differences between transmit and receive frequency.
<br>
The amplitude modulation component of THROB is a raised cosine AM modulation
of each symbol. This combined with two tones transmitted at the same time,
means that a very linear transmitter is required. It also gives the mode its
very unique sound. You will never mistake Throb for any other mode.
<br>
For THROB, nine tones are used, spaced 8 or 16 Hz. For THROBX, 11 tones
are used, spaced 7.8125 or 15.625 Hz.
<br>
Fldigi supports the following:
<br>
\section throb_baud_table Throb baud rates and tone spacings
<br>
Mode | Symbol Rate | Typing Speed | Bandwidth
:------:|:-----------:|:----------------:|:----------------:
THROB1 | 1.0 baud | 1.0 cps (10 wpm) | 72 Hz
THROB2 | 2.0 baud | 2.0 cps (20 wpm) | 72 Hz
THROB4 | 4.0 baud | 4.0 cps (40 wpm) | 144 Hz
THROBX1 | 1.0 baud | 1.0 cps (10 wpm) | 94 Hz
THROBX2 | 2.0 baud | 2.0 cps (20 wpm) | 94 Hz
THROBX4 | 4.0 baud | 4.0 cps (40 wpm) | 188 Hz
<br>
\ref throb_page "Return to Top of Page"
<br>
\ref main_page "Return to Main Page"
*/