W6REK QRSS DTCW

Transmitting from San Jose, Calif (CM97ah): W6REK

Thanks to VE1VDM, ZL2IK, W4HBK, and WA5DJJ for the spectrum grabs.

Grabbed in Nova Scotia by VE1VDM on 30 meter:

Grabbed in New Mexico, USA:

Grabbed in New Zealand by ZL2IK:

My attempt to enhance the signal in that previous image:

Nested (fractal) DTCW:

the inner DTCW with 5 Hz deviation takes under 3 minutes, and is reused multiple times to create the outer DTCW, with 15 Hz deviation, that transmits in about an hour.

Here's the relevant part of that image:

Barely making it to Greensboro NC on 30m:


pi@raspberrypi:~ $ cat -n /usr/local/bin/with-gpio-22.py
     1        import gpiozero, os, sys
     2
     3        # Transmit gpio pin 22 is Active Low for Transmit.
     4        rx = gpiozero.LED(22)
     5
     6        def Transmit():
     7          rx.off()
     8
     9        def Receive():
    10          rx.on()
    11
    12        if len(sys.argv) != 2:
    13          raise Exception('Bad len(sys.argv): %d' % len(sys.argv))
    14
    15        try:
    16                Transmit()
    17                os.system(sys.argv[1])
    18        finally:
    19                Receive()
pi@raspberrypi:~ $

W6REK/4 transmitting from Edgefield County South Carolina

pi@raspberrypi:~ $ cat -n qrss-slashup-sept2018.sh
     1        #!/bin/bash
     2        set -x
     3
     4        function rig() {
     5          rigctl -m 313 -s 9600 -r /dev/serial/by-id/usb-FTDI* "$@"
     6        }
     7
     8        while date
     9        do
    10            set +x
    11            echo WAITING FOR 9/2/5 -- $(date)
    12            while sleep 0.1; do
    13              case $(date +%M) in
    14                *9 | *2 | *5 ) break ;;
    15              esac
    16            done
    17            echo GOT 9/2/5, WAITING FOR 0/3/6 -- $(date)
    18            while sleep 0.1; do
    19              case $(date +%M) in
    20                *0 | *3 | *6 ) break ;;
    21              esac
    22            done
    23            echo GOT IT -- $(date)
    24
    25            case $(date +%M) in
    26              *0 )  F=7038770 ;;
    27              *3 ) F=10138970 ;;
    28              *6 )  F=14095770 ;;
    29              *  )  continue ;;
    30            esac
    31
    32            set -x
    33            rig M USB 2800
    34            sleep 0.2
    35            rig L RFPOWER 0.02
    36            sleep 0.2
    37            rig F $F
    38            sleep 0.2
    39            [ $F = $(rig f) ]
    40
    41            python2 /usr/local/bin/with-gpio-22.py 'set -x;
    42              GOMAXPROCS=1 /usr/local/bin/qrss -gain=0.10 -mode=slashup -secs=8.5 -ramp=1.0 -rate=48000 -base=1000 -base_rand=0 -step=4' |
    43            pacat --format=s16be --channels=1 --channel-map=mono  --rate=48000 \
    44              --device=alsa_output.usb-C-Media_Electronics_Inc._USB_Audio_Device-00-Device.analog-stereo
    45        done
pi@raspberrypi:~ $

2018-09-18:

pi@raspberrypi:~ $ cat -n qrss-slashup-sept2018.sh.3
     1        #!/bin/bash
     2        set -x
     3
     4        function rig() {
     5          rigctl -m 313 -s 9600 -r /dev/serial/by-id/usb-FTDI* "$@"
     6        }
     7
     8        while date
     9        do
    10            set +x
    11            echo WAITING FOR 9/2/5 -- $(date)
    12            while sleep 0.1; do
    13              case $(date +%M) in
    14                *9 | *2 | *5 ) break ;;
    15              esac
    16            done
    17            echo GOT 9/2/5, WAITING FOR 0/3/6 -- $(date)
    18            while sleep 0.1; do
    19              case $(date +%M/%S) in
    20                *0/1? | *3/1? | *6/1? ) break ;;
    21              esac
    22            done
    23            echo GOT IT -- $(date)
    24
    25            case $(date +%M) in
    26              *0 )  F=7038770 ;;
    27              *3 ) F=10138970 ;;
    28              *6 )  F=14095770 ;;
    29              *  )  continue ;;
    30            esac
    31
    32            set -x
    33            rig M USB 2800
    34            sleep 0.2
    35            rig L RFPOWER 0.01
    36            sleep 0.2
    37            rig F $F
    38            sleep 0.2
    39            [ $F = $(rig f) ]
    40
    41            case $(date -u +%d) in
    42             02 | 03 | 05 | 07 | 11 | 13 | 17 | 19 | 23 | 29 | 31 )
    43               python2 /usr/local/bin/with-gpio-22.py 'set -x;
    44                 GOMAXPROCS=1 /usr/local/bin/qrss -gain=0.10 -mode=duo -secs=3.9 -ramp=0.1 -rate=48000 -base=1000 -base_rand=0 -step=3'
    45               ;;
    46             * )
    47               python2 /usr/local/bin/with-gpio-22.py 'set -x;
    48                 GOMAXPROCS=1 /usr/local/bin/qrss -gain=0.10 -mode=slashup -secs=8.5 -ramp=1.0 -rate=48000 -base=1000 -base_rand=0 -step=4'
    49               ;;
    50            esac |
    51            pacat --format=s16be --channels=1 --channel-map=mono  --rate=48000 \
    52              --device=alsa_output.usb-C-Media_Electronics_Inc._USB_Audio_Device-00-Device.analog-stereo
    53        done
    54
    55        # GOMAXPROCS=1 /usr/local/bin/qrss -gain=0.10 -mode=slashup -secs=8.5 -ramp=1.0 -rate=48000 -base=1000 -base_rand=0 -step=4' |
    56        # GOMAXPROCS=1 /usr/local/bin/qrss -gain=0.10 -mode=duo -secs=4.0 -ramp=0.2 -rate=48000 -base=1000 -base_rand=0 -step=3' |