> Didn't seem *too* bad? 4 x 16 bit serial streams with all the I0's, 
> I1's, Q0's, and finally Q1's? A few timing signals too?

We're just angry because we thought (rather naively, I think) we could
turn this into something we could clock in via SPI or a USART. After
struggling with Maxim's horrible documentation and finally seeing the
output stream, we racked our brains with some simple to deal with the
way they serialized the data, and then realized we were going to need a
CPLD anyway.

> So sample slower, and alias down into another nyquist zone.

Yeah, OK, I clearly need to understand this better. I know you can do
this, but I'm really not sure if how I'd do it is right.

> OK, hold it. IF at 2.048 MHz? What happens when you sample a 2.048
> MHz sine wave at 4.096 MHz (draw a diagram to help visualize)?

This is where I wave my hands around in frustration: I totally agree,
this shouldn't work, but then why does everyone else who uses the
MAX2769 uses these settings!!? And I guess it works? It's possible
they're not letting us know what settings they *actually* use in the
real world.... but this is the default setting, and what others claim to

> Pick your sample frequency to be at least 2 x (IF freq + 1 sided
> bandwidth).

That makes sense to me. I'd love to pick your brains a bit more... maybe
*way* *after* your defense :)


Andrew Greenberg

Electrical and Computer Engineering
Portland State University
a...@ece.pdx.edu  C: 503.708.7711

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