new classiccmp.org service

[Scott Stevens]

On Tue, 12 Apr 2005 23:37:52 +0100 (BST)
ard at p850ug1.demon.co.uk (Tony Duell) wrote:

> > 
> > As many of you have probably seen, the ClassicCmp KnowledgeBase has
> > been announced in Evan's Computer Collector Newsletter.
> 
> I've taken a look at it, and I am not yet convinced this is a Good
> Thing...
> 
> In a couple of cases, I disagree with the advice given. I'll give my 
> comments below, and to be honest, they probably are personal comments 
> _but_ it shows there's always room for an alternative viewpoint.
> That's what's great about this list, we have discussions here, nobody
> really tries to be 'God' when it comes to technical matters.
> Alternative ideas help a lot.
> 
> The points I've noticed so far that I disagree with are : 
> 
> 1) Buy a cheap Dial Test Indicator. My view : I am not rich enough to
> buy cheap tools! The point of buying an expensive DTI is not that it
> will last longer (you will not wear out any DTI with normal use!),
> it's that it'll be more accurate. Don't your classic disk drives
> deserve to be set up properly. 
> 
> OK, I use a DTI for other things as well (if you have a lathe it's
> pretty much essential to have one), so perhaps I need a good one.
> But...
> 
> 2) Get a digital storage scope. My view : I've never used a DSO 'in 
> anger', and I've done plenty of debugging. In fact I don't own a DSO.
> Yo ucan do an awful lot with a good analogue 'scope and the DSO always
> 
> worries me in that you don't know what it's done to your signal before
> 
> displaying it. Good DSOs are going to be alright _if correctly used_, 
> cheaper ones may do all sorts of horrors... It's probably like the 
> analogue .vs. digital multimeter debate. I use my Fluke DMM a lot more
> 
> than my analogue VOM but if I could only have one I'd certainly pick
> the analogue one. The reason is that for 99% of repairs accuracy is
> not that important (and on that score , just because a DMM shows 3.5
> digits does not imply they're all meaningful!), but often showing the
> trend of a signal (is it rising or falling, can I adjust for a peak,
> etc), is the important thing. And that's much easier to see on an
> analouge instrument.
> 

If you're fanatical, get a Fluke Differential Voltmeter.  Then you can
'home in' on the DC level with the rotary switches, and watch the analog
variations on the null-detector/indicator.  And late-model Fluke
Differential voltmeters sell for pennies these days on eBay.  And are
truely classic analog hardware (it's the instrument that gave the John
Fluke Company it's good name)