Re: [Discuss-gnuradio] 8 bit samples have an odd spectrum

[Chris Stankevitz]

Matt Ettus wrote:
> Look at the samples in the scope sink.  Do you see a pattern of A A B B 
> C C D D...., meaning instead of unique samples, is every one repeated?  
> If so, it means that the halfband decimator is probably not being 
> bypassed properly.

Here are the first 100 8 bit samples from the USRP and the first 100 16 
bit samples divided by 256.  You'll notice that the 16 bit samples 
divided by 256 are larger than the 8 bit samples.  Both are collecting 
ambient noise from my GPS antenna:

Here are the first 100 8 bit samples from the USRP:
  -2
   0
   0
   0
   2
  -1
   0
   0
   0
  -2
   0
   0
   0
   1
   0
   0
  -1
  -3
   0
   0
   2
   2
   0
   0
   0
   0
   0
   0
  -3
   0
   0
   0
   2
   2
   0
   0
   2
   0
   0
   0
   0
   1
   0
   0
  -3
   0
   0
   0
  -6
   0
   0
   0
  -4
   2
   0
   0
   1
   1
   0
   0
   0
   0
   0
   0
  -2
   0
   0
   0
   3
   0
   0
   0
  -1
  -2
   0
   0
   1
  -3
   0
   0
   0
  -1
   0
   0
   0
  -1
   0
   0
   1
   3
   0
   0
   1
   5
   0
   0
   0
   0
   0
   0

Here are the first 100 16 bit samples divided by 256:
  -1
   3
   2
   2
  -3
  -2
  -3
   1
  -2
   1
  -1
  -1
   1
  -2
   2
   3
  -2
   1
   1
  -4
   0
  -2
  -2
  -3
   0
  -4
   0
  -2
   0
   2
   5
   2
   2
   0
   5
   1
   1
   1
   3
   1
  -2
  -3
  -3
  -5
   1
   3
   0
   0
   4
  -1
   3
   3
   1
  -4
   1
  -2
  -1
  -2
   1
  -6
  -3
  -2
   1
   3
  -4
  -1
  -5
  -2
  -2
   3
   0
  -2
  -1
  -3
   2
   4
   2
   2
   4
  -2
   1
   4
  -1
   1
   1
   3
   0
   0
  -2
  -2
  -3
  -1
   0
   0
  -3
   2
  -3
  -3
  -2
   0