Can anyone please let us know the maximum recording and playback time possible with USRP 2930? Can we use USRP 2930 for recording and playback of say a 2 minute GSM call?
There is no time limit saying the USRP-2930 can only transmit or receive for a limited amount of time. You could definitely run the USRP-2930 for 2 minutes. It depends on how you log your data that determines if you get the 2 minutes worth of data recording.
Check out this record and playback example.
The USRP 2930 can not store any data on itself so the call data will have to be stored on the host. So the maximum duration of the play back data really depends on how much memory you got on the host which is almost infinite.
The USRP 2930 can continuously transmit data for any amount of time provided that you do not encounter underflow errors which might cause discontinuity in the transmission.