![SCS PTC-IIIusb User Manual Download Page 110](http://html1.mh-extra.com/html/scs/ptc-iiiusb/ptc-iiiusb_user-manual_1219876110.webp)
7 Audio
97
Chapter 7
7
Audio
The Audio-denoiser-menu (
aud:-
menu) is activated with the command
AUdio
. The
command prompt takes the form
aud:
.
The following commands are available in the
aud:-
menu:
Bandwith, Center, CWfilter, DD, Delay, Help, Invert, Notch,
Peak, Quit, Through, TOne.
All other (
normal
) commands are not available in the
aud:-
menu!
Quit
or
DD
exit the
aud:-
menu.
The commands of the
aud:-
menu in detail:
7.1
Bandwidth
Default setting: 300
Parameter: X 30... 1000, Bandwith in Hz.
Adjusts the -6 dB bandwidth of the CW-filter continuously between 30 and 1000 Hz.
(Refer also to command
CWfilter
7.2
Center
Default setting: 1400
Parameter: X 300... 2700, center frequency of the CW-filter.
Sets the center frequency of the CW-filter continuously between 300 and 2700 Hz. (Refer
also to command
CWfilter
and the command
CWTerm
, chapter
).
The
Center
command also adjusts the audio frequency of the CW-Terminal (chapter
) of the PTC-IIIusb send and receive sides. (In firmware releases prior to version
1.12, the CW-Terminal used the current Mark-frequency, which sometimes was not
particularly suitable).
7.3
CWfilter
Activates the CW-filter, using the center frequency set by the
Center
command, and the
bandwidth set by the
Bandwidth
command.
The filter is designed as FIR with a linear phase-change, so that even with a bandwidth of
30 Hz it does not ring. The transfer function has not been designed for maximum edge
steepness, but a shape delivering a signal easily readable for the human ear, and the best
signal/noise ratio possible.