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Terminating Unused Output on ADF4351 Eval Board

Question asked by dandober on Sep 19, 2012
Latest reply on Sep 20, 2012 by icollins
Branched from an earlier discussion

Hello; ( how do i start a new post/thread?)

   I have the ADF4351 eval brd and new , out of the box it seems to misbehave. I have one output connected to my 8566A spectrum analyzer  the other is OPEN ...all is well when output is between 3200 and 4400 Mhz for signals between 2200 and 3200 Mhz it has a varitey of ills. WHats up with this? It seems possible the VCO band select is misbehaving? Note: I used supplied program defaults and this occurs, I have tried a number of settings related to band select , no luck. The output seems to be divided , that is at times the freq is correct but its the 4th harmonic, and no I did not mess with divider output and SW reports no divider ( ie set to 1). Also in some places the output just goes crazy, lots of harmonics and wideband noise ( unlocked) ..lastly used the SW sweep function..same thing when it gets between 2200 to 2600 its just a mess. This seems like this should work out of the box, right? All I did was install code anmd plug Eval into USB jack.