[Discuss-gnuradio] TVRX data interface to USRP board (VINN_A, VINP_A; VINN_B, VINP_B)

[HL_Wu]

Hi, all
         This may be a simple question but I can not find any definite answer
from the archive.
         In the module interface, there are two RF data differential pairs from
RF board to the USRP board: VINN_A, VINP_A; VINN_B, VINP_B. 
If there are two individual RF tuners on the RX board, I think they each use 
one different pair, like the picture below for basic RX board.
http://www-personal.engin.umich.edu/~anastas/gnuradio/usrp_gen.eps
But how about the TVRX board? From what I see from the python code,
only one ADC is used. Is one of the differential pairs left open
or both of them connect from the same RF tuner output? If the answer is 2),
under what condition would this be used (I/Q sampling) for this tuner?


Owen Wu
ASMedia