Re: [Discuss-gnuradio] saturation with multi_fft.py

[Eric Blossom]

On Wed, Oct 10, 2007 at 12:50:35PM -0400, address@hidden wrote:
> Eric-
> 
> using -d 160 the problem goes away with this latest build, but remains for 
> higher decimation values.  For example, at decimation of 180, I can 
> reproduce the problem.  As a picture is worth a thousand words, I've put 
> two jpg's up online at:
> 
> www.nd.edu/~ematlis/z.gnuradio/multi_scope_180dec_1.3V.jpg
> 
> www.nd.edu/~ematlis/z.gnuradio/multi_scope_180dec_1.4V.jpg
> 
> The input signal is again a 10 kHz sine wave.  In the first image, the 
> voltage level is 1.3 V p-p.  In the second, 1.4 V p-p.  In both cases I 
> have zero db of gain and decimation of 180, with the LF_RX tuned to 0 Hz. 
> As you can see, at 1.3 V P-P the result is perfect.  However at 1.4 V P-P, 
> the signal is seriously corrupted and jagged.


The second one is showing clipping.  Note how the peaks are folded in
on top of themselves.

Which rbf are you using for these?  std_2rxhb_2tx.rbf (the default),
or std_4rx_0tx.rbf (the one without the halfband).

Can you run the same experiment using the other rbf and post those
pictures too?

The graphs are great.  Thanks for posting the links.

Eric