--- Bill Yakowenko <yakowenk(a)cs.unc.edu> wrote:
> So what kind of wall hanging is more appropriate for a geek?
I have, mounted on a board over the door, a slide rule entitled "In Case Of
Emergency". It was my father's when he was in college.
-ethan
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com
<One plastic box is labeled "Univac memory elements" and has a small sample
<of 3 size cores. The largest is about 1mm O.D. and the smallest is less
<than half that size. They look very fragile as the I.D. is almost as large
<as the O.D.
Those are about the size of the 8E cores.
<The other is a "Indiana General 15 mill memory plane" I guess the cores ar
<15 mill diameter. There are 16 cores wired as a 4x4 plane. The wires are
Big fat ones... not really. Those planes would be easy to drive and
understand. that would be one I'd love to try.
<much smaller than 30 SWG (about 28 AWG). I would say much smaller than 50
<(either) gauge, I need a magnifier just to see them.
I'd have guessed thinner than #40.
Allison
On Apr 20, 16:04, Chuck McManis wrote:
> I'm not sure I parsed this. At my local hardware store the nuts were made
> of Zinc (not steel) and but the washers were made of "soft iron" which I
> thought meant there was a _lower_ carbon content than "steel" washers.
(The
> washers are designed to be compliant whereas the nuts are quite hard)
Zinc isn't a hard metal and it's only weakly ferromagnetic (doesn't stick
to a magnet). The nuts you found are zinc-plated steel, probably what we
call BZP (bright zinc plated). Soft iron sometimes has quite a high carbon
content, and a very variable silicon content (which affects its magnetic
permeability). The composition of "soft iron" varies quite a lot, whereas
although different types of steel have different compositions, the
composition of any given type is fairly standard (and in some cases very
precisely controlled), and usually quite low in silicon.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
On 19 Apr 1999, Richard Erlacher <edick(a)idcomm.com> wrote:
] It's true that may be more interesting when you have different vehicles, but
] if you're trying to determine which of two is faster, don't you focus on
] those two? Having lots of variations in the hardware only tends to muddy
] the water.
Obviously, some of us care about vehicles other than those two.
Doesn't muddy _my_ waters one bit. :-P
I, for one, am interested in processor capabilities independent
of video/disk/etc gorp. Roman numerals isn't going to be a
thorough comparison, but it's better than nothing, and small
enough to be fun. If this is still going on in a month or two,
maybe I'll write an entry myself. As it is now, my schedule
barely allows me to keep up with all the stuff you guys are
writing!
And then, later the same day, regarding my suggestion about
noting the relative ages of processors when comparing their
results, he wrote:
] It's pretty hard to imagine how a limitation like your suggestion would
] apply. Newer processors addressed weaknesses in the older ones. One of
] those was ease of programming. In some cases, e.g. the 6809, the processor
] was designed with a regular instruction set and lots of addressing modes so
] as to make generating code easy. It didn't necessarily make it faster. I
] don't know how elegant such code will ultimately turn out to be.
If you want to get a handle on which processors were really
better than others performance-wise, you look at the best they
can do on some specific problems. Granted, the results may
not be easy to interpret because of varying environmental
characteristics. Welcome to Earth. Nothing is simple here.
Obviously, if the 6809 loses to some older processor, its
adherents can still claim ease-of-coding as a benefit. But it
would still be interesting to know if it could regularly get
whomped by a measly, pathetic, sad-excuse-for-a-processor like
the 6502. :-) :-) :-) :-)
My suggestion was not meant as any sort of limitation, just my
take on what kind of result would be interesting; one way of
interpreting the results. If an older processor doesn't do as
well as the newer one, well, we expected that. But if an older
one outperforms a newer one, there is something worth exploring
there, a lesson to be learned about an improvement really wasn't.
Bill.
Has anyone ever seen a pointer on a Mac start to twitch? Mine seems to
have started jiggleing back and forth slightly. Really disconcerting. Any
ideas on if this is the mouse, or the machine :^(
It seems to have something to do with how the cord is twisted, so I'm
suspecting that the wires are getting a little frayed :^( When I smooth
the cable out, it seems to stop.
Zane
| Zane H. Healy | UNIX Systems Adminstrator |
| healyzh(a)aracnet.com (primary) | Linux Enthusiast |
| healyzh(a)holonet.net (alternate) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| and Zane's Computer Museum. |
| http://www.dragonfire.net/~healyzh/ |
>Am I correct that this is used to connect the UNIBUS backplane in one
>chassis to a UNIBUS backplane in another chassis?
Yes. Do you need any? I have several different lengths here. The -15 is
the length in feet IIRC.
Dan
<I would call 115V 30A a common business circuit; it's certainly exceedingl
<common on minicomputer power controllers. What else do folks plug the
<Twist-N-Locks on their DEC 861C power controllers into?
Special. Most places where I've seen systems installed for the first time
that circuit had to be added. Even at DSG, PK3 and the Mill I had to have
facilities add circuits for some things as that was not the normal
distribution in the lab areas.
My reference was that the average business and building unless prepped
will only have 15 or maybe 20A outlets in place. Older buildings those
will be in short supply. Then again NYC is where I have most of that
experience.
Allison
<generator set up to drive a fast rise time buffer amp (so I can get a
<reasonable amount of current) what else do I need to do to verify that I'v
<successfully "flipped" the device. (My first guess would be a garden
<variety compass)
first you need a waveform that looks like this....
_____|-----|_____________ _______+I
|_____| -I
And put about one turn through the ferrite or steel under test.
Then you'll need a second 1-2 turn loop hooked to the scope.
You'll know the right waveform when the signal starts showing a huge
amplitude difference as switches.
Allison
>First, to get common names:
>Hot = one Phase
>Neutral = Protective Ground
>Ground = Ground (the starpoint on 3 phases connected to earth at the
'generator')
That explains the confusion. In the US:
Hot is one phase and in single phase systems you can and do have 2 hots.
Neutral is what you are refering to as ground. The starpoint for both
single and 3 phase.
Ground is the protective / frame ground.
The protective ground (ground in US codes) is not allowed to normally carry
any current. It should be able to be temporarly disconnected and not create
a hazardous condition.
>Second, do I understand that US appliances got fuses on both wires
>and both are switched ?
On 240 volt equipment yes.
The 120 volt plugs are defined with distinct Hot, Neutral and ground pins.
I am familiar with your plugs also and have wondered how hot / neutral
definitions are handled. Think of US 120V plugs like UK plugs just smaller
and without fuses in them.
>Over here in Germany only one wire is
>switched and protected with a fuse, althrough it is not defined
>which one is the 'hot' line, since our connector is symetrical
>- there is no way to insert the plug in a way where the Hot and
>the Ground side is defined - Our plug isn't inherited from the
>DC times, but rather a new design when 220V AC became standard
>in the 30s, to fit the needs of (and only of) AC Eq.
The US did not used to make a distinction between hot and neutral until
about 30 years ago when they added the "protective" ground pin. Now they
are keyed. If you look closely at a receptacle, one blade is wider -
neutral, The narrower blade is Hot and the round pin is protective ground.
Some "equipment" uses only 2 wires. The blades and often one is larger to
assure that it is polarized correctly. These polarized plugs have come into
common usage in the last 20 years.
Dan
