From: bill.sloman@ieee.org   
      
   On 29/11/2025 8:56 am, Joerg wrote:   
   > On 11/28/25 1:32 PM, Joe Gwinn wrote:   
   >> On Fri, 28 Nov 2025 12:52:07 -0800, Joerg    
   >> wrote:   
   >>   
   >>> On 11/28/25 12:45 PM, Joerg wrote:   
   >   
   > [...]   
   >   
   >>>> To the surprise of my clients it's the contrary. The most   
   >>>> client-shocking redesign was an auto-align circuit for ganged   
   >>>> ADC-channels. High speed, high phase accuracy and all that. They had an   
   >>>> elaborate time domain method with a fat DSP, lots of code and very   
   >>>   
   >>>   I meant they used a frequency domain method.   
   >>>   
   >>>> expensive chips used as programmable delay chips. The NRE alone had   
   >>>> been   
   >>>> humongous. It never reliably converged so the system hung a lot. I   
   >>>> suggested to ditch all that and use time domain. This caused an uproar   
   >>>> because I had rocked the boat a lot and usually consultants aren't   
   >>>> supposed to do that. "I don't think this can possibly work", "It won't   
   >>>> deliver the accuracy", "It won't converge either" and all that.   
   >>>>   
   >>>> Yet the boss let me do it. In the end the whole thing dropped from   
   >>>> three-digit dollars in HW to under 10 bucks. Instead of expensive   
   >>>> discrete-step time delay chips I used inductors, caps and varicap   
   >>>> diodes   
   >>>> for almost infinite granularity. The DSP became unemployed because the   
   >>>> connected PC could easily handle the computations. It converged in less   
   >>>> than a second, always. The NRE was low because it took less than two   
   >>>> weeks of my time and less than a day for the programmer, and we didn't   
   >>>> need an expensive DSP programmer.   
   >>   
   >> Embarrassing.  Were any of the customers design team later   
   >> defenstrated?   
   >   
   > No, they were pretty good. It's the usual phenomenon where, in an old   
   > German saying, you can't see the forest because of all the trees.   
      
   Brainstorming is designed to get around that to some extent, but if you   
   aren't used to thinking outside the box it's difficult to step back far   
   enough to get outside the box.   
      
   > Frequency domain, FFT and all that is the classical approach but   
   > consultants can help companies see other more unorthodox methods.   
      
   Frequently poached from other companies that the consultants have   
   helped. It's not about stealing industrial secrets - just starting off   
   from a different place.   
      
   > Most of my design jobs boil down to that. The other jobs are more boring,   
   > failed EMC tests and such.   
      
   There's nothing boring about EMC.   
      
   --   
   Bill Sloman, Sydney   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)