[Discuss-gnuradio] GNU Radio Companion and noise source

[dennis]

Hello @ all

Sorry for the bad question!
I'm trying to create a simple block with GRC, but i don't know how to do 
this. I want to transmit noise on a specific frequency but only on a 
range of +- 1MHz.

......................................                    
.....................................
| noise source               |                    | 
USRP2-Sink               |
--------------------------------------                    
-------------------------------------
|Type: Gaussian            |                   |Interpolation: 100       |
|Amplitude: 100m (0.1) | --------------> |Frequence: 929.8M     |
|Seed: 42                       |                   |Gain: 
32dB                  |
--------------------------------------                    
--------------------------------------

But my result (shown with usrp_ffty.py) is: The noise is transmitted on 
a wide range (+- 40MHz), because i don't know, how to limit the range 
(and the Gain value doesn't matter...).
I try to insert a "band pass filter" between noise source and USRP2-Sink 
but with no results (what values are correct for low, high cut and 
transition width?).

I hope someone can help me or give me a hint how to do this ;-)

best regards

Dennis Wehrle