Taking some transfer functions of the PDH boxes for the simulink model.  We keep talking about which one has been modified and which hasn't, so at this point I've labelled them box1 and box2 (label on the front panel) so we'll be able to identify them later.  My understanding is that box 1 has been modified by Rana.

First TF below is box 2.  Gain is 4.8 and boost is off.  This is using the agilent without attenuators.

 Second TF is box 1.  Same settings as above.