Reply by Michael A. Terrell●January 28, 20122012-01-28
Robert Macy wrote:
>
> Glad you added "test equipment" Too often THAT is trusted more than
> it warrants!
>
> I embarrassingly once spent 4 hours tracking down, yes, test equipment
> problem, not a circuit problem! Learned a healthy respect to distrust
> EVERYTHING, That even includes distrusting the values marked on the
> components when you breadboard - especially after using 10 ohm
> resistors marked as 1k And, worst of all? a bad lot of IC's! It is
> surprising how much one blindly trusts incoming parts more than they
> trust their own designs to work properly. Now I don't even trust data
> sheets to accurately describe a component. Once, Intel's spec sheet
> was so wrong that my software group worked 6 weeks trying to 'fix'
> their software, all wasted time, all caused by an error in Intel's
> data sheet! When confronted, Intel's response was, oh, yes, that is
> an error. Thanks a lot for the heads up!
>
> All of the above experiences really describe why one should NEVER
> trust a 'garage' design. You know, the design works, so build more
> just like it and start shipping.
>
> After the above experiences, I now trust well worded Buying Contracts,
> and well documented designs with verification testing using test
> equipment traceable to the N??? standards. Now, when you do that;
> THERE is recourse if something doesn't work right.
More than once I was called from my bench to see what was wrong on a
test setup, to find the problem in seconds becasue the tech didn't
follow the procedure to verify the test setup was working. Things like
not bothering to zero the offset voltage on a function generator, then
failing boards becasue the 'video' output was against one rail. It
would piss me off, because I had taught them the proper procedure,
before giving them the product to work on.
--
You can't have a sense of humor, if you have no sense.
Reply by Michael A. Terrell●January 28, 20122012-01-28
Jim Thompson wrote:
>
> Not original with me, I was just quoting qrk's comments to try to
> pound some sense into Jamie... alas, a lost cause... dumb as a stump
> and twice as thick >:-}
I wonder if his employer knows how he looks online. He has mentioned
the company, and it only takes a few seconds to find his public
records. Even a typical low level NDA signed at the time of employment
would be enough legal reason to fire him.
--
You can't have a sense of humor, if you have no sense.
Reply by Jim Thompson●January 26, 20122012-01-26
On Thu, 26 Jan 2012 06:54:40 -0800 (PST), Robert Macy
<robert.a.macy@gmail.com> wrote:
>On Jan 25, 4:15�pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-
>Web-Site.com> wrote:
>...snip...
>> are often wrong. With experience, you will learn a healthy distrust in
>> your simulator and test equipment."
>..snip...
>> � � � � � � � � � � � � � � � � � � � � ...Jim Thompson
[snip]
>
>Glad you added "test equipment" Too often THAT is trusted more than
>it warrants!
>
[snip]
Not original with me, I was just quoting qrk's comments to try to
pound some sense into Jamie... alas, a lost cause... dumb as a stump
and twice as thick >:-}
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Reply by Robert Macy●January 26, 20122012-01-26
On Jan 25, 4:15=A0pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-
Web-Site.com> wrote:
...snip...
> are often wrong. With experience, you will learn a healthy distrust in
> your simulator and test equipment."
> | Voice:(480)460-2350 =A0Fax: Available upon request | =A0Brass Rat =A0|
> | E-mail Icon athttp://www.analog-innovations.com| =A0 =A01962 =A0 =A0 |
>
> I love to cook with wine. =A0 =A0 Sometimes I even put it in the food.
Glad you added "test equipment" Too often THAT is trusted more than
it warrants!
I embarrassingly once spent 4 hours tracking down, yes, test equipment
problem, not a circuit problem! Learned a healthy respect to distrust
EVERYTHING, That even includes distrusting the values marked on the
components when you breadboard - especially after using 10 ohm
resistors marked as 1k And, worst of all? a bad lot of IC's! It is
surprising how much one blindly trusts incoming parts more than they
trust their own designs to work properly. Now I don't even trust data
sheets to accurately describe a component. Once, Intel's spec sheet
was so wrong that my software group worked 6 weeks trying to 'fix'
their software, all wasted time, all caused by an error in Intel's
data sheet! When confronted, Intel's response was, oh, yes, that is
an error. Thanks a lot for the heads up!
All of the above experiences really describe why one should NEVER
trust a 'garage' design. You know, the design works, so build more
just like it and start shipping.
After the above experiences, I now trust well worded Buying Contracts,
and well documented designs with verification testing using test
equipment traceable to the N??? standards. Now, when you do that;
THERE is recourse if something doesn't work right.
Reply by Jamie●January 25, 20122012-01-25
Jim Thompson wrote:
> On Wed, 25 Jan 2012 18:00:04 -0500, "Michael A. Terrell"
> <mike.terrell@earthlink.net> wrote:
>
>
>>Jamie wrote:
>>
>>>Fucking beginner
>>
>>
>> It shows, every time you post something.
>>
>>
>>
>>> What a gas!
>>
>>
>> Stay away from open flames, Maynard. You would burn down the whole
>>trailer park, if you caught fire.
>
>
> Jamie/Maynard/WTF is just one banana peel short of insanity... and yet
> he's smug about it.
>
> He has no clue of the technical competency of 'qrk' who properly
> advised, "Do you blindly trust your models??? If you do, beware, they
> are often wrong. With experience, you will learn a healthy distrust in
> your simulator and test equipment."
>
> I happen to know 'qrk' quite well. His company was a past chip design
> customer of mine. 'qrk' really knows his stuff.
>
> Yet Jamie/Maynard/WTF smart-mouths his superiors. Time to shun him
> into non-existence.
>
> ...Jim Thompson
I am puzzled by you Jim, I really thought you had more common sense
than that.
If seems your above statement is completely contradictory to what I
stated by Ltspice not being reliable, spice in general i guess and bench
equipment is the only truth.
Oh well, I'll just past it off as age on your part. I have an aging
father in-law and I see the resemblance.
Just goes to show how some people are not able to make proper
assessments of others. Most of those generally do not become management.
Jamie
Reply by Jim Thompson●January 25, 20122012-01-25
On Wed, 25 Jan 2012 18:00:04 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:
>
>Jamie wrote:
>>
>> Fucking beginner
>
>
> It shows, every time you post something.
>
>
>> What a gas!
>
>
> Stay away from open flames, Maynard. You would burn down the whole
>trailer park, if you caught fire.
Jamie/Maynard/WTF is just one banana peel short of insanity... and yet
he's smug about it.
He has no clue of the technical competency of 'qrk' who properly
advised, "Do you blindly trust your models??? If you do, beware, they
are often wrong. With experience, you will learn a healthy distrust in
your simulator and test equipment."
I happen to know 'qrk' quite well. His company was a past chip design
customer of mine. 'qrk' really knows his stuff.
Yet Jamie/Maynard/WTF smart-mouths his superiors. Time to shun him
into non-existence.
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Reply by Michael A. Terrell●January 25, 20122012-01-25
Jamie wrote:
>
> Fucking beginner
It shows, every time you post something.
> What a gas!
Stay away from open flames, Maynard. You would burn down the whole
trailer park, if you caught fire.
--
You can't have a sense of humor, if you have no sense.
Reply by Fred Abse●January 20, 20122012-01-20
On Fri, 20 Jan 2012 13:07:00 -0700, Jim Thompson wrote:
> PSpice has a full RLCG model... "TLOSSY" in the parts index.
Didn't know that. LTspice *appears* to have, then you try to use G, and it
tells you to go away.
It appears to be code lifted straight out of Berkeley Spice 3.
--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)
Reply by Jim Thompson●January 20, 20122012-01-20
On Fri, 20 Jan 2012 11:19:40 -0800, Fred Abse
<excretatauris@invalid.invalid> wrote:
>On Fri, 20 Jan 2012 08:16:26 -0800, David Hutchinson wrote:
>
>>
>> The model is the RLCG model for transmission lines.
>>
>> R = resistance
>> L = inductance
>> C = capacitance
>> G = conductance
>>
>> The R and L are in series with the line. The c and G are in parallel.
>> These parameters are on a per-meter basis, multiply by the length dz to
>> obtain the total element value in ohms, henries, farads and siemens.
>>
>
>Most, if not all Spice do not fully implement an RLCG model. The lossy
>line model, LTRA, only implements R, L, and C. Nonzero G not supported
>(yet).
>
>The parameters are on a *per-unit* basis, not per-meter, allowing the use
>of feet, inches, millimeters, cubits, parsecs, whatever.
>
>Examples:
>
>.model RG223 LTRA (LEN=1 R=11.3m L=0.077u C=30.8p)
>
>.model RG59 LTRA (LEN=1 R=51.6m L=0.115u C=20.5p)
>
>Units in this case are per foot.
PSpice has a full RLCG model... "TLOSSY" in the parts index.
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Reply by Fred Abse●January 20, 20122012-01-20
On Fri, 20 Jan 2012 08:16:26 -0800, David Hutchinson wrote:
>
> The model is the RLCG model for transmission lines.
>
> R = resistance
> L = inductance
> C = capacitance
> G = conductance
>
> The R and L are in series with the line. The c and G are in parallel.
> These parameters are on a per-meter basis, multiply by the length dz to
> obtain the total element value in ohms, henries, farads and siemens.
>
Most, if not all Spice do not fully implement an RLCG model. The lossy
line model, LTRA, only implements R, L, and C. Nonzero G not supported
(yet).
The parameters are on a *per-unit* basis, not per-meter, allowing the use
of feet, inches, millimeters, cubits, parsecs, whatever.
Examples:
.model RG223 LTRA (LEN=1 R=11.3m L=0.077u C=30.8p)
.model RG59 LTRA (LEN=1 R=51.6m L=0.115u C=20.5p)
Units in this case are per foot.
--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)