TERMINAL COMMAND for sending a CW TEXT file with UNiXCW/cw program (continuous REPEAT)
while true; do (./cw -d hw:0,1,0 -f ur.txt -w 73 -k 48 -t 852 -v 100); sleep 1; done
for unixcw's CW audio output - this script uses the alsa loopback snd-aloop cable(hw:0,1,0) to receive it uses alsa_in -d hw:0,0,0 using jack audio connection BAY
NOTE: to go above 60 wpm , you have to modify the source code in the libcw.h file and put your own upper limit in place of the "60" BEFORE you compile the source code and build... ./configure make etc....
here is a copy/paste of the mod that i used in the libcw.h file:
/* Limits on values of CW send and timing parameters */
#define CW_SPEED_MIN 4 /* Lowest WPM allowed */ #define CW_SPEED_MAX 200 /* Highest WPM allowed */
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Here is an example of UNIXcw/s CW PROGRAM sending CW at 24 different VLF frequencies for code practice
TCP CLIENT RECEIVER uses QUISK SDR to isolate each VLF signal & demodulate and send to headphones pi4 uses 24 scripts of unixCW/s CW SENDING function to send a text file in cw at 24 different speeds at 24 different VLF frequencies: 500hz, 1500hz, 2500hz, 3500hz, 4500hz etc up to 23500hz pi4
uses 3 snd-aloop loopback cables using their 8 sub channels to send each CW TEXT SEND to its own snd-aloop loopback cable then a single Gstreamer SCRIPT catches all 24 unixCW's snd-loop cables CW and mixes and sends it to a pi4 Gstreamer TCP over iP SERVER using the WAVPACK CODEC
NOTE: some white noise was added for background HF static emulation...
another example using a FREE sound card SDR software from RECRI KEYER to demo the 24 VLF CW signals on a LINUX LAPTOP
SDR software = RECRI KEYER SDR MODULES https://github.com/recri/keyer
a pi4 VLF transmitter is sending 24 VLF CW signals from 500hz to 23500 hz [over ip] to a linux laptop's desktop(via TCP/ip Gstreamer SERVER/client pipelines) Recri Keyer's SDR MODULEs, HiLBERT CeLL, MIXER and FILT demodulate and MIX down the VLF to CW audio