[Discuss-gnuradio] TV_RX anti-aliasing filter

[Nirali Patel]

Hello everyone,

I am a new user and recently set up the USRP and TV_RX boards to receive FM 
radio and now trying to take the dive into capturing HDTV. I had a basic, maybe 
dumb question on the presence of a low pass filter before the A/D converter. 
Does anyone know if the TV_RX board has an anti-aliasing low pass filter on it? 
Or within the Microtune 4937 tuner module? I looked at the schematic for the 
daughter board and the data sheet for 4937 but I am not sure if there is one. 
The TV_RX I got has an IF frequency of 44MHz and I understand that 
undersampling it at 64 Msps with the A/D converter causes it to fold to 20 MHz. 
I wanted to know whether there is or there needs to be a low pass filter before 
the A/D converter to suppress any energy in the lower frequencies before 
sampling.

Thanks,
Nirali Patel
DSP Application Engineer
Coherent Logix, Inc