svdrpsend: 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

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/svdrpsend - from package: vdr

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