Hi,
I am using LMX2571 in PLL mode using internal VCO for synthesising two VHF frequencies. As per the design I need to switch between these two frequencies alternatively in a specified time interval.
For this I have configured F1 and F2 registers for these two separate frequencies respectively and for switching between these two signals, both Trctrl mode and Reg control mode was tried.
By observing the direct output from LMX2571 i.e ( output of RFoutTx & RFoutRx) following result was obtained ;
1. When F1 and F2 was alternatively switched with TrCtrl mode / register select mode - spikes were present in the output spectrum.(snapshot of spectrum attached below)
2. When this F1 and F2 switching was disabled i.e either F1 or F2 is used - there were no spikes in the output spectrum.
Is there any way to remove the spikes from output spectrum for the above mentioned scenario?.