file2afsk

Create AFSK 1200 modulated WAV from a binary file to be transmitted via a handheld FM radio, and vice versa. Example: send and receive SSDV bin image over analog AFSK 1200 modulation from terestrial or VR satellites

Dependencies:

Debian/Ubuntu Linux

sudo apt update
sudo apt install python3 direwolf sox git pavucontrol

Optional:

install SSDV. look at this link for detailed

git clone https://github.com/daniestevez/ssdv
cd ssdv
make
sudo make install

Download the script:

cd ~
git clone https://github.com/hobisatelit/file2afsk.git && cd file2afsk
chmod 755 tx.py rx.py

Configuration:

Config Callsigner

edit tx.py, change SRC_CALL = "ABC" with your actual callsigner

Config Pavucontrol

You only need to set this up once. The goal is for the sox application (audio recorder) and direwolf (KISS server) to be able to listen to the audio output from the speakers or line out of the computer.

Open three terminal

on first terminal run Direwolf KISS server

cd ~/file2afsk
direwolf -c direwolf.conf

on second terminal run

sox -d -r 44100 -c 1 /tmp/test.wav

on third terminal run

pavucontrol

look at Recording tab, you will see direwolf app and sox there, please change capture to MONITOR mode both of them. and then you can close both app with press Ctrl+C on each terminal.

How to convert file into WAV

Run Direwolf KISS server

cd ~/file2afsk
direwolf -c direwolf.conf

on another terminal run

cd ~/file2afsk
./tx.py image.bin

How to convert WAV into file

cd ~/file2afsk
./rx.py

play your recorded wav file or SDR, and the rx.py script will detect the file inside the sound. when finish, press Ctrl+C. the binary file will be saved as .bin file in same directory

How to encode JPG file into SSDV bin

ssdv -e -q 1 image.jpg image.bin

How to decode SSDV bin file into JPG

ssdv -d image.bin image.jpg