xfhell is a GTK+ application for the "fuzzy" digital communication mode
known as Hellschreiber. xfhell has several different built-in fonts in
Adobe BDF format, including a font set for Greek, and a special "short"
font set that is 12 pixels high instead of the standard 14 of the original
Hell fonts. Using this font set would make xfhell incompatible with other
Hellschreiber programs, but the short fonts speed up operation and avoid
wasted bandwidth, inherent in the original Hellschreiber design (an
unavoidable problem of the original mechanical implementation of the mode).
xfhell also has selectable lower baud rate operation (down to 7.6 Bd),
which again make it incompatible with other Hellschreiber programs, but
the lower speeds (especially combined with the 12-pixel fonts) would make
this mode even more efficient and effective.
xfhell has built-in CAT control for the FT847 and FT857 transceivers and a
QSO logging facility similar to xpsk31. It also has a FFT-derived waterfall
display of the incoming signal, with the ability to detect maximum signal
level and tune the transceiver, via CAT, to the appropriate carrier
frequency by clicking near the signal trace.
By default, xfhell wants to install a directory structure in the $HOME of
the installing user. The SlackBuild overrides this, and copies that structure
into /usr/share/xfhell-$VERSION/.