In this case, the receiver attenuation is a direct input with positive values in dB. Therefore SEAMCAT will take the receiver attenuation aVLR(Df) values directly from the function (might be also constant value) that you entered.
aVLR(Df) = blockUse defined (Df) (dB) (Eq. 123)
where Df = (fILT - fVLR)
Figure 390: Illustration of blocking and the associated Blocking Response in a user defined mode
Figure 391: Setting up the blocking response in the user-defined mode