🚀 go-pugleaf

Jon Elson <jme...@wustl.edu> wrote:
> Ahem A Rivet's Shot wrote:
> 
>> On Thu, 15 Mar 2018 07:09:07 -0400
>> J. Clarke <jclarke...@gmail.com> wrote:
>> 
>>> I took that course a few years later and we had an electronic analog
>>> computer, from TI IIRC.  It was kind of fun but by the time I got my
>>> first engineering job digital was "in" and just suggesting the use of
>>> analog anything marked one as some kind of reactionary, at least in
>>> the place I worked.
>> 
>> Makes sense, once a digital computer is fast enough to solve a
>> given problem it will do a more repeatable and reliable job than an
>> analogue computer.
>> 
> Well, there's two kinds of analog computing.  For solving problems in an 
> analytical way, digital has the HUGE advantage that you get the same answer 
> every time, and debugging and documenting what you did is easy.
> 
> However, once the IC op-amp came out, analog computing for production 
> control systems got a huge boost.  Today (and, really, from the late 1980's 
> or so) digital computers with a couple ADC and DAC chips can do a very 
> cheap, reliable, and reproducible job with a minimum of pots and 
> adjustments.  But, back in the 70's and into the 80's you could do a lot 
> with a couple op amps.  I retrofitted a cruise control on a car I had, it 
> was an all analog solution, and worked very well.  About a 2 x 3" PC board 
> with 5 8-pin DIPs and some passives did the whole thing.
> 

ISTM digital solutions are akin to integrating a function that the analog
computer models directly. The more steps you use and the smaller the
interval the closer the digital solution approaches the reality.

-- 
Pete