[Discuss-gnuradio] USRP need antenna?

[Suvda Myagmar]

From FAQ on Ettus website I understood that one doesn't need rf 
front-end to run basic experiments on USRP hardware. Is that correct 
assumption? I have usrp main board and RX, TX daughterboards. I thought 
this hw can tune into frequency spectrum up to 50 MHz, which means I can 
 listen AM radio broadcasts without antenna.

Since I was having trouble running examples such as am_rcv.py provided 
in gnuradio-examples/python/usrp because of wx import issues (see 
separate thread on this issue), I changed the example so that I don't 
use wx module. I tuned into AM stations 1400, 1230 etc. I get the 
following message:

# ./my_am_rcv.py 580
RX d'board A: Basic Rx
RX d'board B: <none>
usrp_standard_rx::set_decim_rate: WARNING rates > 128 result in 
incorrect gain.
>>> gr_fir_ccc: using SSE
>>> gr_fir_fff: using SSE
79
199
Press Enter to quit:

According to this the basic HW I have doesn't seem to be able to handle 
AM radio broadcast frequencies.

-suvda