[sdiy] What is a quadrature oscillator good for?

[Don Tillman]

   > Date: Fri, 12 Sep 2003 11:05:31 -0500
   > From: Grant Richter <grichter at asapnet.net>
   > 
   > Another dumb question, is the assigning of sine and cosine labels
   > arbitrary?  

No, sine and cosine are very well defined mathematically.

For positive frequency, the cosine should be peaking positive as the
sine crosses zero from negative to positive.

For negative frequency, the cosine should be peaking positive as the
sine crosses zero from positive to negative.

So positive frequency is counterclockwise rotation if x is the cosine
and y is the sine.

(... proofreading that about 15 times.)

  -- Don

-- 
Don Tillman
Palo Alto, California
don at till.com
http://www.till.com