Hi,I used a low phase noise signal source as my artiq frequency referenceļ¼The reference frequency is 100MHz This is the phase noise and spectrum of my external 100MHz frequency. But my artiq DDS output frequency produces some other unknown noise besides the sidebands. And his phase noise curve is not very good He looks bad, the frequency of the output produces other noise besides the sidebands. Below is the frequency output and phase noise curve using artiq internal clock reference After artiq connects the external clean source as the frequency reference, the phase noise curve should be better, but it doesn't seem to be, I don't know how to solve this problem, thank you all. I modified refclk=100000000, clk_sel=1, pll_n=40 because the frequency reference I entered is 100MHz.