On Tue, Feb 26, 2002 at 10:36:00AM -0500, Olin Lathrop wrote:
> > The grief saving answer is no. The true answer is "maybe if the conditions
> > are right." Conditions being that the bit rate is slow enough and there
> > isn't drastic changes in temperature.
>
> The absolute bit speed has nothing to do with it.  The relative speed error
> is what matters.  You'd like to be within 3%, whether that's 300 baud +-9,
> or 115.2Kbaud +- 3500.

But if you slow it down then the absolute amount of time before the error
is exceeded is lengthned.

Change your examples to a time scale by inverting:

300 bPS cell width: 3.3333 ms +- 0.3ms
115k bPS cell width: 0.00886805 mS +- 0.000256 ms

There's several orders of magnitude more error available at the slower speed
before you get bit errors.

So yes absolute bit speed does have something to do with it because you
can get proper reception at 300 bPS far outside the error range for 115kbPS.

BAJ

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