Re: [Discuss-gnuradio] What is USRP oscope showing me?

[Chris Stankevitz]

Eric Blossom wrote:
> If this isn't making much sense, try spending some time with Richard
> Lyon's "Understanding Digital Signal Processing".

Eric, all:

First, thanks for your answers.  I'm going to check out the book you 
recommended.  I have "Telecommunication Breakdown" and of course 
wikipedia which are helpful.

Second, I tuned the USRP oscope to 103.3MHz.  I believe the USRP 
downconverted 97.55MHz to 0Hz and 103.3MHz to 5.75MHz.  It clearly 
showed a sine wave which I'm sure is the 103.3 MHz carrier frequency.

I used the graph (see attached) to calculate the frequency to make sure 
it agreed with my 5.75MHz belief.  I counted 10 cycles over 3 divisions:

10 cycles / 3 div
50 us / div = 50e-6 s/div (assuming u is mu)
10 cycles / 3*50e-6 s
10 cycles / 150e-6 s
10/150e-6 Hz
10/150 MHz
1/15 MHz
0.066 MHz

Two orders of magnitude off.

Did I do something wrong?  I'm using TVRX on RXA.

Thank you!

Chris