When I grew hard red winter wheat, and rye, I did my own winnowing in the driveway with a 10 X 10 foot tarp and a 20 inch electric window fan on 3/4 power.
The lighter chaff would carry downwind from the fan, just off the tarp, leaving the berries on the tarp.
With the quinoa, given the seed size, and lite weight, I am unsure how that could be efficiently done without loosing a lot of the seed.
Prior to winnowing, I had hand flailed the wheat with a homemade device of two pieces of wood joined by two interlocking screw-eye pieces of metal hardware.
Perhaps the flail could loosen the seed from the husk/shell (?).
Yeah, I know "dusty"!!
I would just stand offset and upwind from the electric fan.
I actually have a pretty good dehuller that I made. I started with my hand-cranked grain mill, and made plates for it out of a plastic cutting board. Then I glued a textured silicone mat to each plate. They “scrunch” the hulls enough to break them off, but don’t crush the seeds themselves.
On one of my days off, I’m planning to take pictures and write up a how-to about it.