Want DD-DVR + Standard STB to work in 1 connection

Hi,Having 1 BIGTV Standard STB and would like to have new one HD-DVR for same connection.Is there any technical limitation that both would not work with 1 dish antenna?At least Reliance Technical person said there is no issue.Please guide me as i am planning it little soon in this wk only.Thanks,Manish TRIPATHI