how to troubleshoot?

[Philip]

i would build a circut that erything expt resistors is removable(ic sockets) so you just put something in and see if they work

----- Original Message ----- 
From: "Magnus Danielson" <cfmd at swipnet.se>
To: <harrybissell at prodigy.net>
Cc: <Linc at christeld.freeserve.co.uk>; <synth-diy at node12b53.a2000.nl>
Sent: Saturday, January 13, 2001 6:49 PM
Subject: Re: how to troubleshoot?


> From: harry <harrybissell at prodigy.net>
> Subject: Re: how to troubleshoot?
> Date: Sat, 13 Jan 2001 10:40:55 -0500
> 
> > Hi All  (mis me ???)
> > 
> > I'd go with a (gasp) good digital scope, and keep an old analog in reserve
> > for the times when the digital LIES to you... and you need a sanity check.
> > 
> > A tech said to me:  : found the problem... its switcher noise hittinh the dac.
> > What Frequency, I asked?  He didn't know so I went to show him...
> > Measure the period....
> > 
> > Then I noticed that no matter what sweep speed... I got the same number of
> > noise
> > pulses on my screen.  Hmmm.... is this REAL....can it BE ???
> > 
> > Analog scope shows... white noise. Digital was aliasing it into a periodic
> > waveform.
> > 
> > Digital is great for frequency, pulse width, lfo, envelopes... etc.  Roll mode
> > will let
> > you see your .001Hz triangle. NO analog will do that.
> 
> Right. Digital scopes is a mixed blessing. They can do stuff which
> analog jobs just can't do. On the same time, few people really knows
> how a digital scope works on the signal, so they can be confused. I
> still want a modern analog scope next to the digital one. I have some
> old bulky (read tubes) analog scopes elsewhere thought.
> 
> Filestorage is one of the good things about digital scopes. For time
> and frequency measurements a scope is just a tool to know where you
> should trigg.
> 
> Cheers,
> Magnus
>