dst_test: command not found

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/dst_test - from package: dvb-apps

You may install the required package with command apt-get install {package}

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