Hi, i'm an Italian student. I'm using an Oscilloscope with Basic Tx and finding a strange behaviour sending a costant value of 20000. I see a sinusoidal wave generated from Nco (fine modulator) + coarse modulator in this way :
32 MHz -> only coarse -> 670 mVpp 16 MHz -> only coarse -> 730 mVpp .... 0.5 MHz -> only fine -> 680 mVpp 0.1 MHz -> only fine -> 570 mVpp After this frequency, Tension gets down: 12.5 KHz -> only fine -> 148 mVpp 1 KHz -> only fine -> 13.3 mVpp The transfer function on the datasheet shows that with interpolation 4xAD9862 (I'm using Interpolation value of 124 -> 31 (FPGA) * 4 (AD9862) ) it should not be multiplied by the sinc function, so I can't explain the Tension drop after 100kHz. Thanks a lot. Giuseppe Pilla _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
