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Single ended operation in ADL5380 for DC output

We have the eval board of ADL5380. We desire to operate it in a single-ended mode. As suggested in the datasheet the RF and LO input already has a 100pf capacitor connected to one port and ground on the eval board for single-ended mode.  According to the datasheet per pin impedance is 25ohm so in the eval board with the onboard baluns connected do we need to match it at 50ohm since according to the datasheet all the pins are at 25ohm impedance or all are at 50ohm differential. Please correct if any confusion in understanding. 

We have given 5.81Ghz input to RF port at -10dBm and 5.81Ghz input to LO at -5dBm. The board I guess is by default configured to single-ended operation since the SMA connecter not connected to RFIN & LOIN and 100pf already connected. ILO & QLO we have terminated with 50ohm. Is the experiment setup correct or we have to make changes to work in a single-ended configuration? 

We expect a DC signal at the output I and Q single-ended but while observing on the scope but we find the noise at 10mV. We want to observe a DC signal flat line and only the phase difference between the RF and LO. Please correct us if any mistakes and suggest a way to achieve the same. Attaching images of the test setup and observations on the scope for 5.81Ghz at the RF and LO. Using this setup we have also done a trial with 4.7Ghz and 4.8Ghz at the RF and LO respectively to and we could observe 100Mhz signal at around 160mV as shown in the attached image.