At 11:55 AM 2/6/02 -0600, Dave Dribin wrote:
>On Wed, Feb 06, 2002 at 07:34:19AM -0600, Dale Botkin wrote:
> > Absolutely, an analog scope is fine for digital signals.  IMHO a low end
> > analog scope would be far more useful than a low end digital scope, but
> > that's my opinion.
>
>Well, I like that opinion (probably because it's cheaper :).  As long
>as an analog scope is "good enough" for my limited home use, I'd
>rather save the few hundred dollars on PCB manufacturing or something.

I use both analog (Tek 465) and digital (Tek THS-720P) scopes and find I
use the analog scope FAR more often than the digital.  I agree with Dale -
if you have a limited budget, spend it on an analog scope.  But like I
mentioned earlier, buy decent scope probes too.  If you buy a used scope
off eBay, expect to spend as much on probes as you paid for the scope.  I
really can't emphasize enough just how important good probes are.  Stick
with Tek X10 probes unless you get a great deal on Tek X1-X10
probes.  Avoid the cheap import X1-X10 probes - they break easily and just
don't work well.

>BTW, are there any "buyer beware" questions I should ask and signs I
>should look out for while buying a used analog scope?  Are there
>certain parts that always break?  How important is calibration for
>non-critical measurements?

Make sure the trace is bright and focused over the entire screen.  Wiggle
(side to side as well as up & down) all the controls and rotate them over
the whole range - you are looking for noise or bad connections.  Feed a
variable frequency square wave signal into the vertical inputs (DC coupled)
and see just how square it looks.

>Are there certain models that should be avoided due to notriously poor
>quality?

No idea.

>  Are there certain models that are notriously high quality?

Tektronix!  Just excellent!

dwayne


Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax

Celebrating 18 years of Engineering Innovation (1984 - 2002)
  .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-
     `-'   `-'   `-'   `-'   `-'   `-'   `-'   `-'   `-'
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads