Now we use the AD9746 and ADRF6755 to make the modulation,
we found lots of the harmonic of the sample clk, our sample clk is 120MHz,
so we found 240MHz, 480MHz,720MHz...in the spectrum of the rf out of ADRF6755.
the picture is how i connect the AD9746 and ADRF6755.
i have no idea about this issue, pls help me.
Thanks a lot.