Hi All,

I am trying to use this simple 2 port model to help me understand things but have found some odd results from it.

If I set the following parameters in BLKBOX2

S21 = dbpolar(-1.1,0)

S12 = dbpolar(-1.1,0)

S11 = X

S22 = X

ZRef = 50 ohm

then if I sweep X from 0 to 1 and then plot the NF for this the NF drops from 1.1dB gradually to zero when X = 0.473

if I make S22 = 0 but only sweep S11 from 0 to 1 then the NF stays flat at 1.1dB and then drops 'digitally' to 0 when X= 0.473.

This is not making sense to me. Please help

kind regards

marino

I am trying to use this simple 2 port model to help me understand things but have found some odd results from it.

If I set the following parameters in BLKBOX2

S21 = dbpolar(-1.1,0)

S12 = dbpolar(-1.1,0)

S11 = X

S22 = X

ZRef = 50 ohm

then if I sweep X from 0 to 1 and then plot the NF for this the NF drops from 1.1dB gradually to zero when X = 0.473

if I make S22 = 0 but only sweep S11 from 0 to 1 then the NF stays flat at 1.1dB and then drops 'digitally' to 0 when X= 0.473.

This is not making sense to me. Please help

kind regards

marino