Re: The long history of Cinematronics and Vectorbeam

>
> Class-D amplifiers are quite the hit right now, and would get
> my vote for an output stage. Might be a little overkill in complexity
> for a deflection board, however.

Where I work, we're doing brushless DC (oxymoron?) motor control. We've
got a DSP doing current control on all 3 phases with class D amps. It's
actually a simple amplifier, but when you put a current probe on the
scope and look at a phase there is significant (meaning visible but small
compared to the signal) ripple at 20KHz (the PWM freq). Now if a motor
winding isn't enough inductance to cut that off, what makes you think
a monitor yoke is? BTW, you'd probably need to run at an even higher PWM
frequency since you're controlling a display where you can clearly SEE
any noise. Not to say it won't work, but it will be hard to get rid of
the noise and maintain good frequency response - in audio, they are
starting to use class D amps for bass because thats where the most
the power goes AND they can filter out the switching...

-- 
 ___   __   _   _  _
|   \ /  \ | | | || |       phkahler@oakland.edu     Engineer/Programmer
|  _/| || || |_| || |__     " What makes someone care so much?
|_|  |_||_| \___/ |____)      for things another man can just ignore. " -S.H.