[time-nuts] T.I. questions

Chuck Harris cfharris at erols.com
Fri Feb 6 08:29:33 EST 2015


Pulse width modulation.

Suppose the readings go like this:

6,5,5,5,5,5,5,5,5,5,6,5,5,5,5,5,5,5,5,6,5,5,5,5,5,5,5,5,5,5

you would be able to interpolate that result to be 5.1

If it went:

6,6,5,5,5,5,5,5,5,5,6,6,5,5,5,5,5,5,5,5,6,6,5,5,5,5,5,5,5,5

You would be able to interpolate that result to be 5.2

Or:

6,6,6,6,6,5,5,5,5,5,6,6,6,6,6,5,5,5,5,5,6,6,6,6,6,5,5,5,5,5

would be 5.5

and on down the road until you achieved:

6,6,6,6,6,6,6,6,6,5,6,6,6,6,6,6,6,6,6,5,6,6,6,6,6,6,6,6,6,5,...

which would be 5.9

I am certain that I have miscounted somewhere (everywhere?), and
the digits displayed are not required to be so ridged in how they
distribute, just that you are getting ratios between one and the
other.

-Chuck Harris

Bill Hawkins wrote:
> Referring to a 1952 manual on servo systems, jitter seems to be noise
> in the system, while dither is intentionally introduced to get a servo
> through its dead space (usually caused by static friction).
>
> The dead space in a counter is the interval between least significant
> integers.
> Thus the amplitude of the dither is the size of that dead space at a
> frequency
> that will be lost in the average.
>
> I can see how this would work for a servo system, but how can a counter
> display
> more resolution than its least significant digit?
>
> Bill Hawkins
>


More information about the time-nuts mailing list