I just tried several transponders on different satellites, and got different times just about every time, as it automatically re-set the time after being on the transponder for a bit. So short answer, it is not going to work. The best method is to use NTP, if you have it connected to the internet. However. it does not update whenever you turn on the receiver, so every few days you have to update it, as it loses time. I haven't tried the manual setting, but would imagine it too would require periodic updates.