Re: A pleasant surprise

[Joyce Poon <poonj@ecf.utoronto.ca>]

I was flipping through the catalogue this morning (who could resist?) and
read that apparently one can build a speed sensor using a Hall Effect
sensor.  Then I looked up what Hall Effect was, but I'm not sure how to
detect speed with such a sensor still.  Maybe we have to somehow
detect a change in magnetic field of the motor... Hm... Then I visited the
www.seattlerobotics.org website which did not provide much help.  However,
someone wanted to use a Hall Effect sensor to build a compass.  I don't
think we need a compass if we can just keep track of where we are though.

On another note, we can indeed buy Analog to Digital converters on a
single chip, but the cost varies (quite significantly) depending on the
number of output bits (8 vs 12 or even more).

Oh yes, there are lots of filters too.  There is something called a
digital filter (in addition to the EMI <EM interference?> filters).  Does
the computer generate digital garbage?  

Well, so much for now.  I will go through the catalog again later and
prowl on the internet.

Merry Christmas-Eve.  I hope there will be no messages tomorrow (ahem...).

Joyce :)