Forum: GNU Radio sending single tone Am modulated using usrp1+wbx

Hi, I want to transmit and receive a 1kHz cosine tone using dsb am
modulation and usrp1 with 2 wbx dbs, I have connected from  tx/rx output
wbx-a to rx2 input wbx-b with a 50ohm sma cable, Im expecting in scope 
sink
the cosine tone with 1KHz but I have another signal, can you tell me 
what
could be the error?

Im based on the complex envelope theory:   I=Ac(1+m(t))    Q=0

You can see the diagram and the signals on the attached image.

Thanks.