At 09:30 am 22/08/2001 -0600, you wrote:
>There are relatively inexpensive ($20 US) multimeters that can measure
frequency
>up into the tens of megahertz that would be helpful. If you are measuring a
>clock, it will tell you right away whether it's right. It won't tell you
much
>if it's wrong, though. It does give you more information than just measuring
>voltage.
I just had a closer look at mine; I bought it from Halfords (translation
for Statesiders: an auto spares/tools store) and it's got various motor
related functions (an RPM reading and dwell angle measurement thingy), but
I notice it has a frequency reading (Hz, may be a bit oversensitive for
1-2MHz), pulse width (mS) and period (mS) readings. All of these may be
unsuitable for use on a high-speed computer, but I fancy giving them a
go... It can also measure Vac, which is useful for checking transformers...
>Test equipment is expensive, but hardly anyone wants the "old" stuff that
once
>was perfectly adequate for precisely this class of equipment. A 'scope
with two
>probes, delayed sweep timebase, and a bandwidth in excess of 20 MHz (e.g. TEK
>935) is probably adequate. If you shop around, you should have no trouble
>finding a TEK 465 (100 MHz) that's quite complete and functional for
somewhere
>on the order of $250. Over time, these will become less available,
however. My
>old '465 is still the workhorse around my place, though I have faster,
fancier
>models.
This reminds me, a place I used to work at used HP oscilloscopes, c/w
IEEE-488 bus. I don't know if it'd be possible to use a CBM8032 hooked to
an oscilloscope to diagnose a faulty 8032; but it has a nice symmetry about
it :)
>
>As classic hardware ages, it's likely to break and you'll want to be able
to fix
>it, since the technology of the '70's and '80's renders this stuff inherently
>repairable.
>
>It may be painful to learn, but it's very satisfying when you breathe life
into
>what was a "dear, departed" computer from yesteryear.
>
Definitely. And with Z80s (in particular) being so cheap, as well as DRAM
chips, building ones own becomes quite appealing too. I know a chap who
already does that sort of thing (although I think he uses older Intel
processors on the whole); but I like the idea of a 40-pin processor - it's
nice and simple.
I haven't a clue how the bus works though....
Cheers!
Ade.
--
B-Racing: B where it's at :-)
http://www.b-racing.co.uk
Received on Wed Aug 22 2001 - 14:24:49 BST