wsjt: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/wsjt - from package: wsjt

You may install the required package with command apt-get install {package}
Error in other languages:
wsjt: bevel nie gevind nie
wsjt: comandă negăsită
wsjt: comando não encontrado
wsjt: commande introuvable
wsjt: command not found
wsjt: käsku ei ole
wsjt: không tìm thấy lệnh
wsjt: komanda nerasta
wsjt: Kommando nicht gefunden.
wsjt: kommandot finns inte
wsjt: komut yok
wsjt: nie znaleziono polecenia
wsjt: níor aimsíodh an t-ordú
wsjt: no se encontró la orden
wsjt: no s'ha trobat l'ordre
wsjt: opdracht niet gevonden
wsjt: parancs nem található
wsjt: perintah tidak ditemukan
wsjt: príkaz nenájdený
wsjt: příkaz nenalezen
wsjt: команда не найдена
wsjt: командата не е открита
wsjt: 命令找不到
wsjt: コマンドが見つかりません