AD9834 LC Filter

What impedance should have an LC filter connected to IOUT pin of AD9834?

I have a low pass chebyshev filter with a cutoff frequency of 32.5 MHz with 50 ohm impedance designed with http://www.wa4dsy.net/filter/hp_lp_filter.html and built with commercial values

http://img834.imageshack.us/img834/4868/filtrolc.png

Signal without filter is without biasing:

http://imageshack.us/a/img221/723/3mhzdopodds.th.png

But with filter attached signal is distorting.. In image yellow is signal DDS_OUT and blue is DDS_OUT_FILT

http://imageshack.us/a/img600/8315/3mhzprimadopofiltro.th.png

There is a lot of offset, vertical offset of track is shifted to show both tracks.

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