RE: [CAD_CAM_EDM_DRO] bitscope etc

Hi, Lee:

|Been following the discussion about stepper problems, pulse source
|and cable shielding with interest, and I have similar problems. I am
|thinking of adding some equipment like the bitscope
|
|http://www.bitscope.com/
|
|perhaps even an affordable oscilloscope if I can find one, to do some
|trouble-shooting. For a person who is comfortable with science, but
|is not an electronics man would adding those equipment be of any
|help? or would I be better off with just a simple logic probe?
|Talking of logic probe, anyone has built one themself?

If everything goes together and works the first time without any glitches,
you really don't need any test equipment. Unfortunately, I've never been
fortunate enough to encounter this situation in over thirty years of working
on systems.

That being the case, you'll find a logic probe to be quite limited in its
capability. The logic probe can tell you whether or not a point is within
the limits of the legitimate "1" or "0" values. it can also tell you whether
or not the logic level is pulsing (such as the step pulse train) or steady.

However, it does not provide any information to tell you the frequency of
the pulse rate, how steady it is, how wide the pulses are, and how they are
synchronized to another pulse. It cannot tell you how close the logic "1,"
for example is to the threshold for logic level "1," nor can it show any
noise that might be on the lines.

The oscilloscope can provide all of the information as the logic probe. It
can also do all of those items I mentioned that a logic probe cannot do. In
addition, the logic probe monitors one point at a time while a multiple
channel scope can monitor two more points at the same time.

I hope this helps you understand the capabilities of both tools. I have both
a logic probe and an old Heathkit dual channel scope. While setting up my
CNC system, I found myself using the scope, but didn't even connect the
logic probe.

-- Jerry