how to troubleshoot?

[Philip]

Hello
i would make a simple timer ic ......... you could use a bunch of fomrulas or test it at a firendds osc........check the data sheet
anything unclear?
and i have a voltmeter (tube)and i fired it up syncedf whit my digital ....first 1v miss
then i restarted 0.5v wrong then 0wrong(not alteast to my eye) then it worked fine so i first fire up migth not be correcly if it havent been used for a while( this one had 20years+ on it)
// Olsson 
----- Original Message ----- 
From: "Jon Darby" <jdarby at lplizard.com>
To: "Synth-Diy" <synth-diy at node12b53.a2000.nl>
Sent: Monday, January 15, 2001 4:33 PM
Subject: Re: how to troubleshoot?


> Howdy, everyone!
>    Here's a question: I picked up an old tube Heathkit oscilloscope from an
> R/C airplane convention in Pennsylvania a few years ago knowing I would need
> one some day. Well, it seems to work wonderfully, but my eyes are 100%
> untrained in in oscilloscopes, so is there a test procedure I can do to put
> it through its paces and know it is functioning properly? Build a little
> oscillator with known values and frequency maybe? How do you test an
> oscilloscope in general? Is this a stupid question?
> 
> Your pal,
> Jon
> 
> -----Original Message-----
> From: patchell <patchell at silcom.com>
> To: Linc at christeld.freeserve.co.uk <Linc at christeld.freeserve.co.uk>
> Cc: Synth-Diy <synth-diy at node12b53.a2000.nl>
> Date: Saturday, January 13, 2001 12:09 PM
> Subject: Re: how to troubleshoot?
> 
> 
> >    I have a digital scope at work, don't remember the model number, but a
> >500MHz BW, 1GS/s Tek scope.  Real nice scope......BUT....aliasing can be a
> real
> >problem.  A good example is what I am doing right now.  I am trying to
> track
> >down an oscilation in a power amplifier that drives a three phase motor.
> >Depending on how I set the sample rate, the display looks completely
> >different.  The oscilation is about 1MHz and the signal that is supposed to
> >come out is 500Hz.  The oscilation can look real funny, depending on how
> close
> >it happens to be to a ratio of the sample rate.  I generally have to turn
> the
> >sample rate knob (which also sets the equivalent to the sweep rate) in
> order to
> >make sure I get a "good idea" of what is really going on.  I have gone down
> >many blind alleys because I failed to realize that the scope was lying to
> me.
> >Analog scope don't have this problem.  Still, as long as you know that the
> >digital scope will lie, you can be careful.
> >
> >    Personally, my home scope is an analog.  It is only 20MHz bandwidth,
> but
> >that seems to be more than adequate for synth work.
> >
> >    -Jim
> >
> >Lincoln Fong wrote:
> >
> >> >>However if you got cash to spend get a digital so u can upload upload
> the
> >> results to the pc/mac(now were talking 1000$ range)
> >>
> >> I have always used analogue scopes and whilst talking about upgrading the
> >> other day with a friend he mentioned that a good analogue is sometimes
> >> better than a digital. I think it was something to do with the
> quantisation
> >> causing difficulty taking readings(?). Do you scope afficianados have a
> >> preference? Its mainly for audio work which may have an influence. My
> >> current one is 20MHz.
> >> pc uploading is not necessary.
> >>
> >> Lincoln
> >>
> >> Ps without wanting to start another acronym bonanza what does AFAIK stand
> >> for???
> >
> >--
> > -Jim
> >------------------------------------------------
> >* Visit:http://www.silcom.com/~patchell/
> >*-----------------------------------------------
> >*I'm sure glad Merry Christmas comes just once a year
> >* -Yogi Yorgensen
> >------------------------------------------------
> >
>