In the last week Matt and I modified the MFD configuration because the mixer had been illegally used.

Since the output from the comparator is normally about 10 dBm, a 4-way power splitter reduced the power down to 4 dBm in each output port.
In order to reserve a 7 dBm signal to a level-7 mixer, we decided to use an asymmetric power splitter, which is just a combination of 2-way and 3-way splitter shown in the diagram above.
With this configuration we can reserve a 7 dBm signal for a mixer in the fine path.
However on the other hand we sacrificed the coarse path because the power going to the mixer is now 2.2 dBm in each port.
According to the data sheet for the mixer, 1 dB compression point for the RF input is 1dBm. Therefore we put a 1 dB attenuator for the RF port in the coarse system.
In the delay line of the fine path we found that the delay cable was quite lossy and it reduced the power from 2.2 dBm to about 0 dBm.
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