Well it dawned on me after I wrote this that we still need amplitude information so it's back to the drawing board for me :-) The first-derivative equals the limit as delta t goes to zero of:
( F (t + delta t) - F ( t ) ) ) / delta t. So delta t is 3 nanoseconds and the op amp subtracts F(t) from F ( t + delta t ). We therefore have the instantaneous rate of change of the signal. There may be a way to compute everything from that. I don't know yet, so I threw it out there :-) drmail377 wrote: > > > Hi John, > > Just a quick off-the-cuff reply... > > I think you need to consider that delay and true quadrature signals > are not the same. When you delay, you delay for a single frequency, > not the modulation "sidebands" if-you-will. A true quadrature > implementation results in same phase shift for all frequencies of > interest. A passive device example is a quadrature power divider. > Passive quadrature power dividers are always bandwidth-limited. Your > reference to first-derivative reminds me of Group-Delay. Hmmm... > > Be a bit more specific about what you're proposing... > > 73's David > > -- Regards, John ========================================================= email: [EMAIL PROTECTED] photos: http://www.flickr.com/photos/k5jhf/sets/ videos: http://www.youtube.com/profile?user=k5jhf files: http://briefcase.yahoo.com/[EMAIL PROTECTED] web page: http://www.geocities.com/[EMAIL PROTECTED] call sign: K5JHF =========================================================
