Why Are There No Right Angle Traces?

In article <bdl77l$u9m2i$1@ID-100912.news.dfncis.de>,
map.nospam@surfanytime.co.uk says...
"Jim Thompson" <Jim-T@analog_innovations.com> wrote in message
news:j6rrfvcc01pfb6goslqtjrsjpder58clr0@4ax.com...
On Sat, 28 Jun 2003 17:28:59 GMT, onestone <onestone@bigpond.net.au
wrote:

"R. Steve Walz" wrote:

BM wrote:

I was told the other day that there are no right angle traces on PCBs
(the
traces go to something like 45 degrees between perpendicular traces)
because
of something to do with something or other. Could something please
explain
this or point me to some resources so I can book up.

Thanks

-BM
------------
Because the electrons slide off the copper if they take the corners
too fast! ;-> No, it's because chemical etching rounds off sharp
corners quite destructively, as it presents more side of the trace
to the etchant per lineal than a rounded one does.


Nearly right! The ones on the outside of any corner have to travel
faster than the ones on the inside. If the corner is 45 degrees or less
this is OK, since the outside ones don't have to travel faster than C
unless the track is wider than 100mils. But the transition is so sharp
on a right angle corner that the outside ones have to break the C
barrier on any track wider than 6 mils. The problem is that this is no
longer legal, having been banned by Albert E. Thus the outside electrons
are forced to crowd the inner lanes. Since they have already been
accelerated more than the inner electrons they carry more inertia, and
it's actually the inside electrons that get bumped. They then scramble
around to the other side of the track and try to jump back on, hence the
illusion that they have slipped from the outer edge.

Al

Not quite ;-) But current crowding does occur in corners. There was
a paper by Jim Dunkley on this subject, rigorously deriving the
current density in corners, clear back in the mid 1960's.

...Jim Thompson

Indeed, that is to be expected. The electrons are charged, so they repel
their neighbours. They can only change direction or move if there is an
inbalence in forces, so they will tend to bunch up at the corner and push
adjacent electrons around it. There is therefore an increased density of
electrons at the corner, and a high electric field as a result.
Notwithstanding this the direction is being changed as they turn 90 degrees
which is an acceleration, and accelerating electrons radiate. Anyway, that's
how I look at it!
Click to expand...
Have you done the measurements or the calculations? If not, your
"feelings" are rather unimportant.

Let me ask, how fast do electrons travel? What is their kinetic
energy? Is this important? If so, when?

--
Keith
 
In article <bdleo8$d93$1@news7.svr.pol.co.uk>, nospam@nospam.com
says...
"BM" <brandon(underscore)melland@hotmail.com> wrote in message
news:1L0La.1667$7e.1222@nwrddc04.gnilink.net...
I was told the other day that there are no right angle traces on PCBs (the
traces go to something like 45 degrees between perpendicular traces)
because
of something to do with something or other. Could something please explain
this or point me to some resources so I can book up.

Thanks

-BM


People tend to be lazy when judging something a PCB technically, so they go
for the appearance. An aesthetically pleasing PCB gives the impression that
who ever layed it out is intelligent enough to lay it out correctly.
Click to expand...
I'll buy that. Let's call it marketing one's self. How much
money is put into packaging breakfast cereal?

--
Keith
 
On Sun, 29 Jun 2003 02:30:31 +0100, "jmcA" <nospam@nospam.com> Gave
us:

"BM" <brandon(underscore)melland@hotmail.com> wrote in message
news:1L0La.1667$7e.1222@nwrddc04.gnilink.net...
I was told the other day that there are no right angle traces on PCBs (the
traces go to something like 45 degrees between perpendicular traces)
because
of something to do with something or other. Could something please explain
this or point me to some resources so I can book up.

Thanks

-BM


People tend to be lazy when judging something a PCB technically, so they go
for the appearance. An aesthetically pleasing PCB gives the impression that
who ever layed it out is intelligent enough to lay it out correctly.
Jason
Click to expand...
Very true, but for some circuits, even at low frequencies, it makes
a difference. I will attempt to illustrate why the details matter in
electronics with a couple examples. One directly topic related, and
one closely related, but more toward workmanship in the industry.

Take a small HV supply, and lay out two PCBs, one with right angle
traces, and one with curved transitions or 45s utilized. Both PCB
assemblies get potted, so corona at the corners will not be an issue
here.

Testing the two boards will indicate noise characteristics in the 90
degree PCB that are greater in amplitude than the other two PCB
choices for the second board.

The reason is crosstalk. Another would be trace path lengths.

Either way, the 90 degree board will exhibit poorer, noisier
performance. If it is a regulated circuit, the likelihood of that
noise getting injected into the control loop(s) of the circuit are
high, causing poorer operation.

Another example of why the details matter:

A tester could not determine why he had higher leakage currents on
an assembly after it was potted than before.

Our chief engineer said "That's easy... Clean the board."

The guy couldn't believe it. I said that so much as breathing
"coffee breath" onto an HV assembly can cause failure modes and
particularly leakage (I learned it from the master tho). After
utilizing a vapor phase degreasing method for cleaning the unit in
question, the leakage currents read pre and post pot were reported by
him to be identical. He was "flabbergasted" (whatever/wherever that
comes from). I knew it, as I too didn't believe them to be so
sensitive some years back in my early HV realm experiences.

It is always important to clean PCB assemblies that involve high
impedance control or monitoring loops as it is quite easy to introduce
stray flows into places where they are not desired. Merely touching a
1G Ohm resistor with one's finger will render it useless.

SMD assemblies are of particular importance in control loops. Make
sure any resistor changes are followed by thorough spot cleaning with
a dabber, then a solvent, then forced air. One can spend hours trying
different value resistors, wondering why the math isn't working.

One only wants the electrons to flow in only the desired places, and
only in the desired ways. :-] *THEN* the math works... (mostly).

Anyway, today's PCB plot methods use round spots such that corners
even at right angles have a radius on the outside edge that matches
the trace width usually. 90 degree corners would probably not suffer
the same etch process problems, but would most assuredly still posses
many of the electrical gremlins associated with such structural shapes
where current flow is concerned.

I have taken the time to lay out boards with curved transitions all
around, yet still following the shortened path 45 methods for the most
part. Absolutely no sharp inside or outside corners were on it
though.

Great for HV stuff. Don't forget to "Bump Solder" all of your cap
and diode nodes on your HV multiplier boards! Round solder ball
shapes are a good thing. :-]
 
"Keith R. Williams" wrote:
In article <bdleo8$d93$1@news7.svr.pol.co.uk>, nospam@nospam.com
says...

"BM" <brandon(underscore)melland@hotmail.com> wrote in message
news:1L0La.1667$7e.1222@nwrddc04.gnilink.net...
I was told the other day that there are no right angle traces on PCBs (the
traces go to something like 45 degrees between perpendicular traces)
because
of something to do with something or other. Could something please explain
this or point me to some resources so I can book up.

Thanks

-BM


People tend to be lazy when judging something a PCB technically, so they go
for the appearance. An aesthetically pleasing PCB gives the impression that
who ever layed it out is intelligent enough to lay it out correctly.

I'll buy that. Let's call it marketing one's self. How much
money is put into packaging breakfast cereal?

--
Keith
Click to expand...
More than the cost of the food put in the multicolor pasteboard box.
--


Michael A. Terrell
Central Florida
 
Blake Leverett wrote:

John Larkin wrote:


The two best PCB layout people I've known were both women. And they
were very concerned about how the boards looked.

I have done layout on a lot of boards. To me, looks really do count, both
on placement and routing. No self-respecting layout person would create
an
ugly board. They don't call it "artwork" for nothing. Also, having
unnecessary vias is just plain wrong. Even though it really doesn't
matter most times, I spend times to make the board look like it was
purposefully
designed. If it looks "pooped out" it probably was.

I remember once the boss was going to lay out a board himself. It was all
in 90deg traces. Ugly as hell, and didn't work - not because of traces,
but because of other errors.
Click to expand...
As Albert Einstein already said that only a beautifully looking formula
can be a correct formula (I don't remember the exact phrase),
only a beautifully looking piece of hardware will function flawlessly.

Of course, we all know that this is not necessarily true. I don't know
whether there are some statistics available, but I think there is
at least some truth inside.

Apart from all the technical issues involved (i.e. in this case by
right angle turns), a designer that does not put any attention on the
appearance of his design, does probably also not put much attention
on the general design as well. As a result, it will show up some flaws.
Therefore we might have some coincidence here.

I think this does not only apply to electronics.

Regards,
Mario


----------------------------------------------------------------------
Digital Force / Mario Trams Mario.Trams@informatik.tu-chemnitz.de
Mario.Trams@wooden-technology.de
Chemnitz University of Technology http://www.tu-chemnitz.de/~mtr
Dept. of Computer Science Tel.: (+49) 371 531 1660
Chair of Computer Architecture Fax.: (+49) 371 531 1818
----------------------------------------------------------------------
 
Chuck Simmons wrote:
markp wrote:

"Keith R. Williams" <krw@attglobal.net> wrote in message
news:MPG.196ab5755c6fe94298a4f3@enews.newsguy.com...
In article <bdq43n$vrp3q$1@ID-100912.news.dfncis.de>,
map.nospam@surfanytime.co.uk says...
snip
Time dilation was shown in the orbits of the above bodies.


Time dilation theory was used to explain the discrepency between
calculated orbits and observed orbits. This magnitude of this
discrepency could have been perturbed by other bodies, and the
overall measurement was not that accurate anyway. This doesn't
contitute a proof IMO, only consistency.

Nonsense. Postulating "other bodies" influence on Mercury in the
20th century would have been along the same lines as proposing
the come-back of "epicycles". There was a known error, though
one not accounted for by Newtonian physics. Einstien plugged the
hole.

Einstein postulated a possible cause for this perihelion shift. He
came up with something that seems to "plug the hole" but this
doesn't make his theory right or complete. This difference was just
consistent with his theory IMO, nothing else. There will always be
an error in measurements, and Mercury is inherently difficult to
measure, and there could well have been, and be, other bodies
influencing it, however small its magnitude.

Just to set the record straight, the total perihelion advance of
Mercury is of the order of 4500 arcseconds per century. Of this
total, 45 arcseconds per century was anomolous. This was known in the
19th century. This was not, however, the motivation for GR. GR plugs
an even nastier hole in Newtonian physics. It eliminates the need for
the idea of absolute space. Special Relativity did not do this. In
any event, Eddington's confirmation of the bending of light passing
near the sun was a more important confirmation of GR. The bending was
half what is predicted by Newtonian theory and thus in line with GR.
Click to expand...
Er..Ahmmm.. this is not a good one either. It appears that this
particular "confirmation" is not really supportable. There errors of the
measurement were not low enough. Of course, the bending of light has
been confirmed with much better precision nowadays.



Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.
 
Kevin Aylward wrote:
Chuck Simmons wrote:
markp wrote:

"Keith R. Williams" <krw@attglobal.net> wrote in message
news:MPG.196ab5755c6fe94298a4f3@enews.newsguy.com...
In article <bdq43n$vrp3q$1@ID-100912.news.dfncis.de>,
map.nospam@surfanytime.co.uk says...
snip
Time dilation was shown in the orbits of the above bodies.


Time dilation theory was used to explain the discrepency between
calculated orbits and observed orbits. This magnitude of this
discrepency could have been perturbed by other bodies, and the
overall measurement was not that accurate anyway. This doesn't
contitute a proof IMO, only consistency.

Nonsense. Postulating "other bodies" influence on Mercury in the
20th century would have been along the same lines as proposing
the come-back of "epicycles". There was a known error, though
one not accounted for by Newtonian physics. Einstien plugged the
hole.

Einstein postulated a possible cause for this perihelion shift. He
came up with something that seems to "plug the hole" but this
doesn't make his theory right or complete. This difference was just
consistent with his theory IMO, nothing else. There will always be
an error in measurements, and Mercury is inherently difficult to
measure, and there could well have been, and be, other bodies
influencing it, however small its magnitude.

Just to set the record straight, the total perihelion advance of
Mercury is of the order of 4500 arcseconds per century. Of this
total, 45 arcseconds per century was anomolous. This was known in the
19th century. This was not, however, the motivation for GR. GR plugs
an even nastier hole in Newtonian physics. It eliminates the need for
the idea of absolute space. Special Relativity did not do this. In
any event, Eddington's confirmation of the bending of light passing
near the sun was a more important confirmation of GR. The bending was
half what is predicted by Newtonian theory and thus in line with GR.


Er..Ahmmm.. this is not a good one either. It appears that this
particular "confirmation" is not really supportable. There errors of the
measurement were not low enough. Of course, the bending of light has
been confirmed with much better precision nowadays.
Click to expand...
It is better than you think. The anomolous perihelion advance is known
to +-0.45 arcseconds per century and is 45.11 arcseconds per century.
The GR value is 43.03 arcseconds per century. The remaining error may be
either a need for a more accurate theory or errors in the less well
known numbers in the GR calculation. The measured number must be
considered accurate to at least the stated error band.

The precision of astrometric measurements is so high that these are the
best confirmations of the theory aside from radar measurements.

Chuck
--
... The times have been,
That, when the brains were out,
the man would die. ... Macbeth
Chuck Simmons chrlsim@webaccess.net
 
In article <5bt1gvckpsp3tb9qmoqm43tdosbmmfo29b@4ax.com>,
DarkMatter@thebarattheendoftheuniverse.org says...
On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?


Eat shit and die, wussy boy.
Click to expand...
Wow, you have been studying!

Score: Three-letter words = 4
Four-letter words = 1 (impressive and original)
Five letter words = 1 (most impressive)

Average word length = 3.5 (First-grade level, perhaps)

--
Keith
 
Chuck Simmons wrote:
Kevin Aylward wrote:

Chuck Simmons wrote:
markp wrote:

"Keith R. Williams" <krw@attglobal.net> wrote in message
news:MPG.196ab5755c6fe94298a4f3@enews.newsguy.com...
In article <bdq43n$vrp3q$1@ID-100912.news.dfncis.de>,
map.nospam@surfanytime.co.uk says...
snip
Time dilation was shown in the orbits of the above bodies.


Time dilation theory was used to explain the discrepency between
calculated orbits and observed orbits. This magnitude of this
discrepency could have been perturbed by other bodies, and the
overall measurement was not that accurate anyway. This doesn't
contitute a proof IMO, only consistency.

Nonsense. Postulating "other bodies" influence on Mercury in the
20th century would have been along the same lines as proposing
the come-back of "epicycles". There was a known error, though
one not accounted for by Newtonian physics. Einstien plugged the
hole.

Einstein postulated a possible cause for this perihelion shift. He
came up with something that seems to "plug the hole" but this
doesn't make his theory right or complete. This difference was just
consistent with his theory IMO, nothing else. There will always be
an error in measurements, and Mercury is inherently difficult to
measure, and there could well have been, and be, other bodies
influencing it, however small its magnitude.

Just to set the record straight, the total perihelion advance of
Mercury is of the order of 4500 arcseconds per century. Of this
total, 45 arcseconds per century was anomolous. This was known in
the 19th century. This was not, however, the motivation for GR. GR
plugs an even nastier hole in Newtonian physics. It eliminates the
need for the idea of absolute space. Special Relativity did not do
this. In any event, Eddington's confirmation of the bending of
light passing near the sun was a more important confirmation of GR.
The bending was half what is predicted by Newtonian theory and thus
in line with GR.


Er..Ahmmm.. this is not a good one either. It appears that this
particular "confirmation" is not really supportable. There errors of
the measurement were not low enough. Of course, the bending of light
has been confirmed with much better precision nowadays.

It is better than you think. The anomolous perihelion advance is known
to +-0.45 arcseconds per century and is 45.11 arcseconds per century.
The GR value is 43.03 arcseconds per century. The remaining error may
be either a need for a more accurate theory or errors in the less well
known numbers in the GR calculation. The measured number must be
considered accurate to at least the stated error band.
Click to expand...
I was referring to the bending of light, not the proof of the absence of
the planet Vulcan. imo, a rational examination of Eddington's experiment
is that it meant nothing.

Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.
 
On Tue, 01 Jul 2003 11:22:46 GMT, Spehro Pefhany <speff@interlog.com>
wrote:

On Mon, 30 Jun 2003 16:37:42 -0700, the renowned John Larkin
jjlarkin@highSNIPlandTHIStechPLEASEnology.com> wrote:

I wish I had an FEA tool to do things like this. Does anybody know if
Sonnet Lite does area resistance analysis?

OK, a bad snap of Steve's fax has been posted to a.b.s.e.

Thanks. Looks like it was a messy derivation for some poor grad
student(?).

If you do a dumb estimate by drawing a line through the center of the
conductors you get 0.707 for the corner rather than 0.559. If you've
got a serpentine pattern with lots of corners and not much
straightaway it could be significant, but with the example given it's
only 0.8% different.

There's a fluffy article in the June issue of InTech magazine in which
they claim that carbon nanotubes may eventually be useful in IC design
because they can handle current densities of 10^6 A/cm^2 without
deterioration.

Best regards,
Spehro Pefhany
Click to expand...

Copper IC metallization is already operating in the MA/cm^2 range. The
whole nanotech/buckyball/nanotube thing is massively overhyped.
Somebody is claiming a nanotube-based RAM...

http://www.economist.com/science/displayStory.cfm?story_id=1763552

which just about pins my bogometer needle.

John
 
On Tue, 1 Jul 2003 11:16:01 -0400, Keith R. Williams
<krw@attglobal.net> wrote:

In article <5bt1gvckpsp3tb9qmoqm43tdosbmmfo29b@4ax.com>,
DarkMatter@thebarattheendoftheuniverse.org says...
On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?


Eat shit and die, wussy boy.

Wow, you have been studying!

Score: Three-letter words = 4
Four-letter words = 1 (impressive and original)
Five letter words = 1 (most impressive)

Average word length = 3.5 (First-grade level, perhaps)
Click to expand...
Sno-o-o-o-ort! ROTFLMAO!

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| Jim-T@analog_innovations.com Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

For proper E-mail replies SWAP "-" and "_"

Get Lolita Out of Debt... Add Three Inches to Your Mortgage!
 
On Tue, 01 Jul 2003 08:31:27 -0700, the renowned John Larkin
<jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote:

Copper IC metallization is already operating in the MA/cm^2 range. The
whole nanotech/buckyball/nanotube thing is massively overhyped.
Somebody is claiming a nanotube-based RAM...

http://www.economist.com/science/displayStory.cfm?story_id=1763552

which just about pins my bogometer needle.
Click to expand...
I take it you're not likely going to be investing in the inevitable
IPO..

"Mr. Schmergel won't say exactly how Nantero's chips will work, but he
says they will use an electromechanical approach to storing memory
instead of electrical charges."

http://www.redherring.com/vc/2001/1031/390020439.html

Founding Team:

Greg Schmergel
Co-founder, President & CEO. Greg Schmergel was most recently Senior
Vice President, Corporate Strategy for About, Inc., the 5th largest
Web property. Previously he was President and CEO of
ExpertCentral.com, Inc.

http://www.nantero.com/fteam.html

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
On Tue, 01 Jul 2003 16:34:38 GMT, Spehro Pefhany <speff@interlog.com>
wrote:


I take it you're not likely going to be investing in the inevitable
IPO..
Click to expand...

I happen to know some of the VCs who are funding this, and have seen
the sort of corporate paperwork they like. I assure you that nobody
(not the employees with options, not the angel investors, likely not
the founders) but the VCs will get anything but screwed.

John
 
Kevin Aylward wrote:
Chuck Simmons wrote:
Kevin Aylward wrote:

Chuck Simmons wrote:
markp wrote:

Einstein postulated a possible cause for this perihelion shift. He
came up with something that seems to "plug the hole" but this
doesn't make his theory right or complete. This difference was just
consistent with his theory IMO, nothing else. There will always be
an error in measurements, and Mercury is inherently difficult to
measure, and there could well have been, and be, other bodies
influencing it, however small its magnitude.

Just to set the record straight, the total perihelion advance of
Mercury is of the order of 4500 arcseconds per century. Of this
total, 45 arcseconds per century was anomolous. This was known in
the 19th century. This was not, however, the motivation for GR. GR
plugs an even nastier hole in Newtonian physics. It eliminates the
need for the idea of absolute space. Special Relativity did not do
this. In any event, Eddington's confirmation of the bending of
light passing near the sun was a more important confirmation of GR.
The bending was half what is predicted by Newtonian theory and thus
in line with GR.


Er..Ahmmm.. this is not a good one either. It appears that this
particular "confirmation" is not really supportable. There errors of
the measurement were not low enough. Of course, the bending of light
has been confirmed with much better precision nowadays.

It is better than you think. The anomolous perihelion advance is known
to +-0.45 arcseconds per century and is 45.11 arcseconds per century.
The GR value is 43.03 arcseconds per century. The remaining error may
be either a need for a more accurate theory or errors in the less well
known numbers in the GR calculation. The measured number must be
considered accurate to at least the stated error band.


I was referring to the bending of light, not the proof of the absence of
the planet Vulcan. imo, a rational examination of Eddington's experiment
is that it meant nothing.
Click to expand...
Yes. The effect to be measured was close to 1 arcsecond and the probable
error was about 0.25 arcsecond. It was a start. Much of the error was
due to having to leave the camera in position for some months in order
to get several night time plates of the same stars. The focal length of
the camera changed slightly due to temperature change from the time of
the eclipse to the time when the night plates were taken. Today, the
optical experiment can be done to milliarcseconds without an eclipse and
without waiting for months to get baseline stellar positions. The radar
experiments are even better.

Chuck
--
... The times have been,
That, when the brains were out,
the man would die. ... Macbeth
Chuck Simmons chrlsim@webaccess.net
 
On Tue, 01 Jul 2003 14:27:26 -0500, Jackson Harvey
<jharvey@bermai.com> Gave us:

DarkMatter wrote:

On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?

Eat shit and die, wussy boy.

"Feces" would work better, I think.
Click to expand...

EFAD sounds better than ESAD as well.
 
In article <nva4gvsroaoo5mfsfvbqtgeqilr4np2502@4ax.com>,
DarkMatter@thebarattheendoftheuniverse.org says...
On Tue, 01 Jul 2003 14:27:26 -0500, Jackson Harvey
jharvey@bermai.com> Gave us:

DarkMatter wrote:

On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?

Eat shit and die, wussy boy.

"Feces" would work better, I think.


EFAD sounds better than ESAD as well.
Click to expand...
Bigger words? Did you buy a Thesaurus?

You continue to impress me dimmie!

--
Keith
 
On Tue, 1 Jul 2003 22:54:15 -0400, Keith R. Williams
<krw@attglobal.net> Gave us:

You continue to impress me dimmie!
Click to expand...

Yer a Ditz. You don't get impressed, you get awed by every little
thing.
 
On Tue, 01 Jul 2003 14:27:26 -0500, Jackson Harvey
<jharvey@bermai.com> wrote:

DarkMatter wrote:

On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?

Eat shit and die, wussy boy.

"Feces" would work better, I think.
Click to expand...
Consume Feces and decease, wussy shaveling.

Average word length: 6.

:)
 
On Tue, 01 Jul 2003 22:53:45 -0700, the renowned DarkMatter
<DarkMatter@thebarattheendoftheuniverse.org> wrote:

On Wed, 02 Jul 2003 04:02:29 GMT, Carl D. Smith
cdsmith69NOSPAM@earthlink.net> Gave us:

On Tue, 01 Jul 2003 14:27:26 -0500, Jackson Harvey
jharvey@bermai.com> wrote:

DarkMatter wrote:

On Mon, 30 Jun 2003 22:03:34 -0400, Keith R. Williams
krw@attglobal.net> Gave us:


Good, you know two-letter words and we know you have a grasp on
four-letter words, perhaps you'd like to try some three and five
letter words?

Eat shit and die, wussy boy.

"Feces" would work better, I think.

Consume Feces and decease, wussy shaveling.

Average word length: 6.

:)


Machinate Horseshit, and depart this mortal coil.
Click to expand...
Expire through coprolitic mastication.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
On Wed, 02 Jul 2003 04:11:23 GMT, Tom Woodrow <tomwoodrow@comcast.net>
wrote:

This an old thread but I can't resist adding my 2 cents.

1. Don't know about when they did PCB artwork with Pen and Ink,
Click to expand...
NASA insisted on it, at least for the stuff on Saturn V. They were
concerned about tape creeping or peeling. It was amazingly tedious,
worse than tape-on-mylar if you can imagine that. Everything was
nicely curved and filletted, too.


2. When laying out a PCB using moderate to high voltage, the last thing
you wanted was a sharp point or corner in your artwork "unless" you
desired to create a spark gap.

3. It made for ugly artwork

4. In the old days when you hand taped an artwork, it usually took two
people to check the artwork for errors. One would read the schametic and
one would verify traces went to the correct points. Tracing nested
square corners was very hard on the eyes.
Click to expand...
What a pain. I still like to draw schematics with a Berol Turquoise on
vellum (then I let the kids CAD it for me) but I'll never get
nostalgic about taping boards. I remember two, three weeks of leaning
over a hot light table, holding my breath every time I had to lay a
line between two IC pads. I remember discovering that we'd have to
move a whole section left 150 mils. I love PADS... I can slouch in my
chair, latte in one hand and mouse in the other.

John
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top