Re: Speaking of Scopes....

Sean,

First off, a scope is nothing more than a voltmeter that shows what
happens to voltage versus time. What you want in a good scope are
three things; a sharp focus, good writing speed and an excellent
trigger.

A sharp focus lets you see the fine details of the signal you are
looking at; the glitch in a waveform that may be double-triggering
some logic circuitry that's misbehaving.

Good writing speed is for some event that may happen only 1 in 10,000
times. The scope has to be bright enough to display that event though
it may occur for 10uS out of every 1/10 of a second.

An excellent trigger is one that you can move on a complex repetative
signal, yet be able to clearly see it synchronise on the screen. Most
scopes really fall short in this regard.

A good scope is a marvelous instrument, but like any instrument, it
is dependent on the user to interpret what it shows and what that
means. It is no better than the person using it.

Any practicing EE would be blind without a scope, it is literally
his "eyes" when it comes to seeing what a circuit is doing.

It takes time, but it is not difficult to learn what it means that
you are seeing, it does take practice though. It's just a voltmeter
that shows what's happening to voltage versus time.

Mariss

--- In CAD_CAM_EDM_DRO@y..., "audiomaker2000" <audiomaker@s...> wrote:
> ...
> I've been thinking of getting one for my shop (one from this
century
> anyway).
>
> What would be the attributes of an o'scope that I should look for?
>
> I would like to use it for (learning how to) diagnose CNC
equipment,
> audio gear (amps, processors, etc), automotive, shop electrical,
etc..
>
> I have bunches of Fluke VOM's, and I was thinking I'd sell them and
> get something like this:
>
> http://fluke.com/products/features.asp?SID=11&AGID=4&PID=8221
>
> or the 196 or 199 scopemeter.
>
> It would be great to still have a portable product, but I'm not
sure
> about the LCD screens and other possible drawbacks to this type of
> unit over just keeping my VOM's and getting a bench type analog
scope?
>
> In whichever scope I get, what spec's would I need. I'm not NASA,
> but I'd like a unit that could do the test that the smart guy on
the
> ttech phone line would like me to do.
> Since I'm also not an electronics wiz... the Flukes can print, or
> capture the screens for distribution to places like *this* for
> examination by those who know better than I (a really great feature
I
> think).
>
> Thoughts?
> Sean