Looking ahead here at what we are getting into.  With enough samples
to recover from a mistake, this is something I noted.  If someone
better knows  whats up in this chip than I have figured here, then help
us with that insight.

  Looking at the inputs to the AD8333 Evaluation Board Circuit Diagram
it shows that they each have a + / - input as if they are all balanced
inputs?  If this is so, I am seeing then that the input from the
antenna to CH1 and CH2 will need to come from a toroid with two in
phase secondary windings.

  The LO IN is depicted also as having what looks like a balanced
input.  And likewise may need to be fed with a toroid secondary.  This
I suppose then is the first thing to check on the breakout boards.

  The inputs all seem to be depicted in the evaluation board schematic
as having "DC isolation capacitors" on each side of the presently
"assumed" balanced inputs.  So the toroid secondaries can not be such
that they allow direct current to pass from the + to -.  

  In figure 13 of the Analog Devices AD8333 PDF, the capacitors are
depicted as CH1 = C22, C23, LO IN = C15, C16, CH2 = C19, C20.

  These inputs also look allot like Linear Integrated IC inputs?  I
don't think this is what this is.  So I am thinking that these are
hence balanced inputs with DC blocking isolation across them.

  The I/Q outputs also have two lines going out and this seems for
Linear Integrated IC amplifiers in this case.  So I guess when we get
that far we will see what we have to do then.  I need to go and look up
the various IC types and become re~acquainted with which are what here.

  With Gilbert Cells I can easily imagine this being so, having
balanced inputs and outputs.  And we will then need two toroids for
this IC.

  I have the ARRL HB on CD Rom here and can look up the Gilbert Cell
and post that here.

  


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