Math and electrical desgin

[bitrex]

On 3/28/2020 12:45 PM, bitrex wrote:

On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

I would say other books like that are, in the audio-world Douglas Self's
books on power amp and small-signal audio design, the Bracewell book on
the Fourier transform in the dsp-world, "Modern C++ Design" by Andrei
Alexandrescu in the programming-world, and of course AoE III free plug!
free plug!

 

Rick C <gnuarm.deletethisbit@gmail.com> wrote in
news:7fc284f5-421c-43f1-b21c-b7c9f1c8aef2@googlegroups.com:

On Saturday, March 28, 2020 at 11:09:16 AM UTC-4, Mike Coon wrote:
In article <r5lujd$1pt7$1@gioia.aioe.org>,
DecadentLinuxUserNumeroUno@decadence.org says...

It is not an uninterruptible power supply. It is a
microprocessor.
Need the Latin Mu symbol Âľ And you knew that. You're just
lazy.

And you are just intentionally setting out to annoy the Greeks by
calling "symbol Âľ" "Latin"!

Imagine how it makes the Latinos feel too!

Well, in the same VANE (haha)... you fucked that one up too.

See if we can't get that vane shoved up yer ass and see how latino
you think it feels then. Ooops... that would make it worse.

You probably think that song is about you...

I am going to go drain the main vein now...

 

[George Herold]

On Saturday, March 28, 2020 at 1:04:46 PM UTC-4, jla...@highlandsniptechnology.com wrote:

On Sat, 28 Mar 2020 12:50:02 -0400, bitrex <user@example.net> wrote:

On 3/28/2020 12:45 PM, bitrex wrote:
On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

I would say other books like that are, in the audio-world Douglas Self's
books on power amp and small-signal audio design, the Bracewell book on
the Fourier transform in the dsp-world, "Modern C++ Design" by Andrei
Alexandrescu in the programming-world, and of course AoE III free plug!
free plug!

If I were to count how many times a book is pulled off the shelf and
used, the winner would be the Williams filter book. After that,
Reference Data For Radio Engineers, for the wire size and screw thread
tables. AoE fairly often too.

My "Building Scientific Apparatus" has the wire gauge table book marked.
GH

--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[George Herold]

On Friday, March 27, 2020 at 3:29:36 PM UTC-4, blo...@columbus.rr.com wrote:

A topic to elicit some thoughts....

How important is mathematics to you as an engineer? Do you consider yourself an applied mathematician? I would say that I do. As an analog designer how much do you use various mathematical concepts. Basic electronic circuit design does not seem to require a lot of theoretical math, where as, signal processing requires a lot of math.

I have been working , on and off, to really try to understand linear algebra. I am on my 3rd pass ( of the first 10 lectures) of Gilbert Strangs on-line MIT course. I think I am finally getting it. I really want to know linear algebra because I want to be good at matlab which is rooted in linear algebra. However, is linear algebra used in circuit design other than an occasional solving of two or three simultaneous equations?

Linear algebra, as in matrix manipulation?
V=I*R is linear algebra. :^)
Is the online course from a math prof.?
I always enjoy the math more when it's partially applied.
I had a course on 'advanced engineering math' taught by an
engineer (evening classes) And it was great. I really like a
concrete 'thing' to stick my equations to.

George H.

My chosen area is more RF/radio engineering. On the radio side, the signal processing stuff is definitely math intensive and required to be good at it.
Theoretical EMAG is important, but you can go a long way without being super proficient at maxwells equations.

How is advanced math used in circuit design....I mean where an engineer cannot accomplish his task with out the math?

This post is intended to get some fairly on topic discussion going.

 

[Joerg]

On 2020-03-28 10:04, jlarkin@highlandsniptechnology.com wrote:

On Sat, 28 Mar 2020 12:50:02 -0400, bitrex <user@example.net> wrote:

On 3/28/2020 12:45 PM, bitrex wrote:
On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

I would say other books like that are, in the audio-world Douglas Self's
books on power amp and small-signal audio design, the Bracewell book on
the Fourier transform in the dsp-world, "Modern C++ Design" by Andrei
Alexandrescu in the programming-world, and of course AoE III free plug!
free plug!

If I were to count how many times a book is pulled off the shelf and
used, the winner would be the Williams filter book. After that,
Reference Data For Radio Engineers, for the wire size and screw thread
tables. AoE fairly often too.

I agree except for the Williams. It used to be heavily used here but is
now on the book shelf in the next office. Because the computer kind of
took over filter design.

So now it's the bible, AoE, Unitrode IC Data Handbook, A Practical Guide
to Linux, VLSI Design, a J&J first aid kit, then lots of my own binders.
In that order.

Oh, anbd one of my binders contains the brwing recipes.

--
Regards, Joerg

http://www.analogconsultants.com/

 

[George Herold]

On Friday, March 27, 2020 at 6:25:46 PM UTC-4, pcdh...@gmail.com wrote:

How important is mathematics to you as an engineer?  
Do you consider yourself an applied mathematician?  
I would say that I do.  As an analog designer how much do you
use various mathematical concepts.

A lot of what I do is (a) for a given electro-optical design concept, calculate how good it _could_ be, (b) figure out how to get there, and (c) if that's a win, proceed, but if not, think up something better and goto(a).

Significant amounts of math are required to get a good result, as well as a lot of lore and old fashioned crank-turning.

My favorite type of math is 'back of the envelope' calculations.
Those are fun... but it is always better with one or two other
people. (you can sorta check each other..)

George H.

Cheers

Phil Hobbs

 

[Joerg]

On 2020-03-27 12:29, blocher@columbus.rr.com wrote:

A topic to elicit some thoughts....

How important is mathematics to you as an engineer?

It ranks surprisingly low on the pecking order.

... Do you consider yourself an applied mathematician? ...

Definitely not. My sister (has a mathematics degree) is razzing me about
that all the time but that's just how I am. IMO engineering is mostly
instinct. People who don't have them can't be good engineers. Instinct
comes with practice, lots of practice.

... I would say that I do. As an
analog designer how much do you use various mathematical concepts.

I look them up if needed

The rest is done by SPICE.

Basic electronic circuit design does not seem to require a lot of
theoretical math, where as, signal processing requires a lot of
math.

I think it requires a lot of gut feel, more so than math. The math comes
later when fine-tuning stuff or when deriving a transfer function. The
latter is sometimes tough for me. Start solving a lengthy equation,
reach end of line, turn paper sideways, formula grows and grows, still
not enough length, tape another paper to the right side, pencil lead
breaks off again, cuss a little ...

I have been working , on and off, to really try to understand linear
algebra. I am on my 3rd pass ( of the first 10 lectures) of Gilbert
Strangs on-line MIT course. I think I am finally getting it. I
really want to know linear algebra because I want to be good at
matlab which is rooted in linear algebra. However, is linear algebra
used in circuit design other than an occasional solving of two or
three simultaneous equations?

My honest opinion after over four decades of analog design is that
linear algebra is not super-important when designing circuits. Way more
important is constant "radar vision", looking for potential pitfalls,
noice sources, stability issues, SOAs, margins and, very important, have
a cost calculator run inside the brain all the time.

My chosen area is more RF/radio engineering. On the radio side, the
signal processing stuff is definitely math intensive and required to
be good at it.

Sorry, but I don't really agree and RF is my home turf. I learned a lot
more from ham radio than in all the course at the university and not a
lot of math was involved.

... Theoretical EMAG is important, but you can go a long
way without being super proficient at maxwells equations.

True ... but ... one must have a very good gut feel of how Maxwell
applies to stuff. Otherwise the whole design could turn into a nightmare
at the EMC lab.

How is advanced math used in circuit design....I mean where an
engineer cannot accomplish his task with out the math?

It does happen but rarely. For example, when you need to decide whether
to switch from frequency domain to time domain as I just had to do on a
project. That required a boatload of math and solving. Can't say that I
particularly enjoyed that part of the project but as John Wayne used to
say, man's got to do what man's got to do.

This post is intended to get some fairly on topic discussion going.

Now, about the virus and the election ...

--
Regards, Joerg

http://www.analogconsultants.com/

 

On Saturday, March 28, 2020 at 3:55:53 PM UTC-4, George Herold wrote:

On Friday, March 27, 2020 at 3:29:36 PM UTC-4, blo...@columbus.rr.com wrote:
A topic to elicit some thoughts....

How important is mathematics to you as an engineer? Do you consider yourself an applied mathematician? I would say that I do. As an analog designer how much do you use various mathematical concepts. Basic electronic circuit design does not seem to require a lot of theoretical math, where as, signal processing requires a lot of math.

I have been working , on and off, to really try to understand linear algebra. I am on my 3rd pass ( of the first 10 lectures) of Gilbert Strangs on-line MIT course. I think I am finally getting it. I really want to know linear algebra because I want to be good at matlab which is rooted in linear algebra. However, is linear algebra used in circuit design other than an occasional solving of two or three simultaneous equations?
Linear algebra, as in matrix manipulation?
V=I*R is linear algebra. :^)
Is the online course from a math prof.?

This online course is from Gilbert Strang, who I think I can say, is considered one of the world experts in fundamental Linear Algebra.

The thing that is tough about linear algebra is that there are not a lot of applications that continually reinforce your expertise on the subject. We use simple algebra all the time. It gets constantly reinforced. With linear algebra, you learn the various concepts , which are quite difficult - or at least hard to sort it all out, and then it does not seem like there a lot of applications for the --get er done - type of engineer. I am convinced though, that mastery of the subject will allow new insights into different problems.

I always enjoy the math more when it's partially applied.
I had a course on 'advanced engineering math' taught by an
engineer (evening classes) And it was great. I really like a
concrete 'thing' to stick my equations to.

George H.

My chosen area is more RF/radio engineering. On the radio side, the signal processing stuff is definitely math intensive and required to be good at it.
Theoretical EMAG is important, but you can go a long way without being super proficient at maxwells equations.

How is advanced math used in circuit design....I mean where an engineer cannot accomplish his task with out the math?

This post is intended to get some fairly on topic discussion going.

 

[George Herold]

On Saturday, March 28, 2020 at 12:46:01 PM UTC-4, bitrex wrote:

On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

My copy is pretty worn and dog-eared by this point but I can't seem to
find it on Amazon anymore.

Abebooks is good for that type of stuff.


George

 

On Saturday, March 28, 2020 at 4:23:14 PM UTC-4, Joerg wrote:

On 2020-03-27 12:29, blocher@columbus.rr.com wrote:
A topic to elicit some thoughts....

How important is mathematics to you as an engineer?


It ranks surprisingly low on the pecking order.


... Do you consider yourself an applied mathematician? ...


Definitely not. My sister (has a mathematics degree) is razzing me about
that all the time but that's just how I am. IMO engineering is mostly
instinct. People who don't have them can't be good engineers. Instinct
comes with practice, lots of practice.


... I would say that I do. As an
analog designer how much do you use various mathematical concepts.


I look them up if needed

The rest is done by SPICE.


Basic electronic circuit design does not seem to require a lot of
theoretical math, where as, signal processing requires a lot of
math.


I think it requires a lot of gut feel, more so than math. The math comes
later when fine-tuning stuff or when deriving a transfer function. The
latter is sometimes tough for me. Start solving a lengthy equation,
reach end of line, turn paper sideways, formula grows and grows, still
not enough length, tape another paper to the right side, pencil lead
breaks off again, cuss a little ...


I have been working , on and off, to really try to understand linear
algebra. I am on my 3rd pass ( of the first 10 lectures) of Gilbert
Strangs on-line MIT course. I think I am finally getting it. I
really want to know linear algebra because I want to be good at
matlab which is rooted in linear algebra. However, is linear algebra
used in circuit design other than an occasional solving of two or
three simultaneous equations?


My honest opinion after over four decades of analog design is that
linear algebra is not super-important when designing circuits. Way more
important is constant "radar vision", looking for potential pitfalls,
noice sources, stability issues, SOAs, margins and, very important, have
a cost calculator run inside the brain all the time.


My chosen area is more RF/radio engineering. On the radio side, the
signal processing stuff is definitely math intensive and required to
be good at it.


Sorry, but I don't really agree and RF is my home turf. I learned a lot
more from ham radio than in all the course at the university and not a
lot of math was involved.


Notice how I said RF/radio. It is the radio part - modulation that requires the math stuff. About ten years ago I realized that I could not really call myself a radio engineer if I did not have the basics of DSP down. Most of the radio - except power amplifiers/antennas and LNAs is getting done in DSP. It is a tough mountain to climb, but I just could not shake the idea that I could not call myself a radio engineer (in today's world---professionally) if I did not understand DSP.

There is a lot more tools to understand this stuff than there was 15 years ago, and things like gnu radio are quite amazing.

And then the next problem, how do you be a player in radio - DSP - if you are not good at software (I am not - but I do want to learn the gnu radio cadence of programming).

... Theoretical EMAG is important, but you can go a long
way without being super proficient at maxwells equations.


True ... but ... one must have a very good gut feel of how Maxwell
applies to stuff. Otherwise the whole design could turn into a nightmare
at the EMC lab.


How is advanced math used in circuit design....I mean where an
engineer cannot accomplish his task with out the math?


It does happen but rarely. For example, when you need to decide whether
to switch from frequency domain to time domain as I just had to do on a
project. That required a boatload of math and solving. Can't say that I
particularly enjoyed that part of the project but as John Wayne used to
say, man's got to do what man's got to do.


This post is intended to get some fairly on topic discussion going.


Now, about the virus and the election ...

--
Regards, Joerg

http://www.analogconsultants.com/

 

On Friday, March 27, 2020 at 6:00:10 PM UTC-4, Rick C wrote:

On Friday, March 27, 2020 at 3:29:36 PM UTC-4, blo...@columbus.rr.com wrote:
A topic to elicit some thoughts....

How important is mathematics to you as an engineer? Do you consider yourself an applied mathematician? I would say that I do. As an analog designer how much do you use various mathematical concepts. Basic electronic circuit design does not seem to require a lot of theoretical math, where as, signal processing requires a lot of math.

I have been working , on and off, to really try to understand linear algebra. I am on my 3rd pass ( of the first 10 lectures) of Gilbert Strangs on-line MIT course. I think I am finally getting it. I really want to know linear algebra because I want to be good at matlab which is rooted in linear algebra. However, is linear algebra used in circuit design other than an occasional solving of two or three simultaneous equations?

My chosen area is more RF/radio engineering. On the radio side, the signal processing stuff is definitely math intensive and required to be good at it.
Theoretical EMAG is important, but you can go a long way without being super proficient at maxwells equations.

How is advanced math used in circuit design....I mean where an engineer cannot accomplish his task with out the math?

This post is intended to get some fairly on topic discussion going.

Math is the foundation of all science and engineering.

That said, if you aren't building the foundation, you can use fairly basic math and git 'er done!

Once in a while I actually use calculus. I've sometimes used differential equations. I use very basic forms of abstract algebra which includes Post algebras which includes Boolean algebra. But more than all the others put together what I use is basic algebra. I can't say I've knowingly used linear algebra although some of the things I've learned may well be part of that.

So your work is not so much circuit design as it is system design?

I like to think I straddle circuits and systems. I am decent at both but certainly not an expert at analog. The problem in my company is that there is not enough work in circuit design to keep one always busy. I also think that most circuit problems are better solved through a system approach. If you get the system concept wrong, then the circuit is going to be wrong. If you know what you want at the high level, it is easier to tell if your circuit design is adequate.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[Flyguy]

On Saturday, March 28, 2020 at 2:01:15 PM UTC-7, jla...@highlandsniptechnology.com wrote:

On Sat, 28 Mar 2020 13:06:24 -0700 (PDT), George Herold
ggherold@gmail.com> wrote:

On Friday, March 27, 2020 at 6:25:46 PM UTC-4, pcdh...@gmail.com wrote:
How important is mathematics to you as an engineer?  
Do you consider yourself an applied mathematician?  
I would say that I do.  As an analog designer how much do you
use various mathematical concepts.

A lot of what I do is (a) for a given electro-optical design concept, calculate how good it _could_ be, (b) figure out how to get there, and (c) if that's a win, proceed, but if not, think up something better and goto(a)..

Significant amounts of math are required to get a good result, as well as a lot of lore and old fashioned crank-turning.

My favorite type of math is 'back of the envelope' calculations.
Those are fun... but it is always better with one or two other
people. (you can sorta check each other..)

George H.

Cheers

Phil Hobbs

We play a game, in a meeting, of doing the math in our heads. To
slide-rule sort of accuracy, not many digits, but close enough to see
what matters.

We've got pretty good at it, so we can really impress visitors.



--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

Personally, it was vital. Not all the time, but when math is needed there is no substitute. Try explaining complex impedance to someone w/o math; it just won't make any sense. Or how a capacitor can conduct current. Or how a transformer works. Or how RF signal transmission works. Had a discussion once with an FAA person on why radar can pick up non-metallic objects like birds - it pretty much ended when I mentioned "dielectric constant." It really becomes indispensable when you start designing control systems or advanced signal analysis.

 

On Sat, 28 Mar 2020 13:04:54 -0700, Joerg <news@analogconsultants.com>
wrote:

On 2020-03-28 10:04, jlarkin@highlandsniptechnology.com wrote:
On Sat, 28 Mar 2020 12:50:02 -0400, bitrex <user@example.net> wrote:

On 3/28/2020 12:45 PM, bitrex wrote:
On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

I would say other books like that are, in the audio-world Douglas Self's
books on power amp and small-signal audio design, the Bracewell book on
the Fourier transform in the dsp-world, "Modern C++ Design" by Andrei
Alexandrescu in the programming-world, and of course AoE III free plug!
free plug!

If I were to count how many times a book is pulled off the shelf and
used, the winner would be the Williams filter book. After that,
Reference Data For Radio Engineers, for the wire size and screw thread
tables. AoE fairly often too.


I agree except for the Williams. It used to be heavily used here but is
now on the book shelf in the next office. Because the computer kind of
took over filter design.

I look at the attenuation and step response curves, to see what type
and order of filter is, basically, emotionally appealing. I can't
really quantify how pretty I want a pulse to look vs rise time vs
cost. I take a normalized prototype from Williams, scale it, plug into
Spice and fiddle for standard values and beauty. Some programs design
vanilla active and passive filters around standard value parts, but
not around the parts that I have in stock.

So now it's the bible, AoE, Unitrode IC Data Handbook, A Practical Guide
to Linux, VLSI Design, a J&J first aid kit, then lots of my own binders.
In that order.

Oh, anbd one of my binders contains the brwing recipes.

I have job binders that I use frequently, but they go down in the
basement archives when a design is over.





--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[George Herold]

On Saturday, March 28, 2020 at 4:04:44 PM UTC-4, Joerg wrote:

On 2020-03-28 10:04, jlarkin@highlandsniptechnology.com wrote:
On Sat, 28 Mar 2020 12:50:02 -0400, bitrex <user@example.net> wrote:

On 3/28/2020 12:45 PM, bitrex wrote:
On 3/27/2020 6:28 PM, pcdhobbs@gmail.com wrote:
+1 on Wes Hayward

That's the first time I've agreed with T. Bit this year.

Cheers

Phil Hobbs


Very good book, it was definitely over my head when I first picked up a
copy about 12 years ago (bedridden due to illness at the time ironically
enough, thankfully that passed) and I had to come back and approach it
repeatedly to start pulling "ahhhhh I sees" out of it but it paid off
eventually.

Like jamming with a musician who's much more experienced than you but
still fairly down-to-earth Hayward is the kind of author that tries to
really pull you up to his level whether you want to or not.

I would say other books like that are, in the audio-world Douglas Self's
books on power amp and small-signal audio design, the Bracewell book on
the Fourier transform in the dsp-world, "Modern C++ Design" by Andrei
Alexandrescu in the programming-world, and of course AoE III free plug!
free plug!

If I were to count how many times a book is pulled off the shelf and
used, the winner would be the Williams filter book. After that,
Reference Data For Radio Engineers, for the wire size and screw thread
tables. AoE fairly often too.


I agree except for the Williams. It used to be heavily used here but is
now on the book shelf in the next office. Because the computer kind of
took over filter design.

So now it's the bible, AoE, Unitrode IC Data Handbook, A Practical Guide
to Linux, VLSI Design, a J&J first aid kit, then lots of my own binders.
In that order.

Oh, anbd one of my binders contains the brwing recipes.

--
Regards, Joerg

http://www.analogconsultants.com/

I'll second AoE as most used.
GH

 

On Sat, 28 Mar 2020 13:06:24 -0700 (PDT), George Herold
<ggherold@gmail.com> wrote:

On Friday, March 27, 2020 at 6:25:46 PM UTC-4, pcdh...@gmail.com wrote:
How important is mathematics to you as an engineer?  
Do you consider yourself an applied mathematician?  
I would say that I do.  As an analog designer how much do you
use various mathematical concepts.

A lot of what I do is (a) for a given electro-optical design concept, calculate how good it _could_ be, (b) figure out how to get there, and (c) if that's a win, proceed, but if not, think up something better and goto(a).

Significant amounts of math are required to get a good result, as well as a lot of lore and old fashioned crank-turning.

My favorite type of math is 'back of the envelope' calculations.
Those are fun... but it is always better with one or two other
people. (you can sorta check each other..)

George H.

Cheers

Phil Hobbs

We play a game, in a meeting, of doing the math in our heads. To
slide-rule sort of accuracy, not many digits, but close enough to see
what matters.

We've got pretty good at it, so we can really impress visitors.



--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[Phil Hobbs]

On 2020-03-28 16:06, George Herold wrote:

On Friday, March 27, 2020 at 6:25:46 PM UTC-4, pcdh...@gmail.com wrote:
How important is mathematics to you as an engineer?
Do you consider yourself an applied mathematician?
I would say that I do.  As an analog designer how much do you
use various mathematical concepts.

A lot of what I do is (a) for a given electro-optical design concept, calculate how good it _could_ be, (b) figure out how to get there, and (c) if that's a win, proceed, but if not, think up something better and goto(a).

Significant amounts of math are required to get a good result, as well as a lot of lore and old fashioned crank-turning.

My favorite type of math is 'back of the envelope' calculations.
Those are fun... but it is always better with one or two other
people. (you can sorta check each other..)

Designing something cool with a few smart people at a whiteboard is the
most fun you can have standing up.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Clifford Heath]

On 29/3/20 8:22 am, Flyguy wrote:
> ...when math is needed there is no substitute. Try explaining complex impedance to someone w/o math; it just won't make any sense. Or how a capacitor can conduct current. Or how a transformer works. Or how RF signal transmission works. Had a discussion once with an FAA person on why radar can pick up non-metallic objects like birds - it pretty much ended when I mentioned "dielectric constant." It really becomes indispensable when you start designing control systems or advanced signal analysis.

That's because you aren't very good at explaining things. Feynman used
to say that anything he couldn't explain to an undergraduate in ten
minutes was something he didn't actually understand.

I have successfully explained all the things in your examples to
complete science-illiterates. It's possible, but you need to find the
right entry point.

CH

 

[Clifford Heath]

On 29/3/20 9:27 am, Joerg wrote:

On 2020-03-28 15:19, Rick C wrote:
On Saturday, March 28, 2020 at 6:08:43 PM UTC-4, Joerg wrote:
On 2020-03-28 13:38, blocher@columbus.rr.com wrote:
On Friday, March 27, 2020 at 6:00:10 PM UTC-4, Rick C wrote:

[...]


So your work is not so much circuit design as it is system
design?

I like to think I straddle circuits and systems.  I am decent at
both but certainly not an expert at analog.  The problem in my
company is that there is not enough work in circuit design to
keep one always busy.  I also think that most circuit problems
are better solved through a system approach.  If you get the
system concept wrong, then the circuit is going to be wrong.  If
you know what you want at the high level, it is easier to tell if
your circuit design is adequate.


Amen!

Top-down is generally the only approach that really works. Now
we'll have to explain that to the next generations. All the ones
who have served in the military don't need to be told, they know
this already.

There are very few times when a pure top down approach is used.


In medical and aerospace all the time. Has to be that way, else you can
land in hot water with the Federales. Without a top-down approach it is
hard to maintain a proper design history file set.

Right, but I agree with Rick, in that top-down design only works where
you know for each of the required bottom-up elements, what is possible
to implement.

I will avoid estimating or committing to a system design until I go away
and research and/or prototype key technological elements. I got away
with that in the face of financial managers asking for "certainty" by
saying "I can't give you an estimate, but here's an estimate of how long
it till take to do the pre-work required to get you a good estimate".

Clifford Heath

 

[George Herold]

On Saturday, March 28, 2020 at 5:01:15 PM UTC-4, jla...@highlandsniptechnology.com wrote:

On Sat, 28 Mar 2020 13:06:24 -0700 (PDT), George Herold
ggherold@gmail.com> wrote:

On Friday, March 27, 2020 at 6:25:46 PM UTC-4, pcdh...@gmail.com wrote:
How important is mathematics to you as an engineer?  
Do you consider yourself an applied mathematician?  
I would say that I do.  As an analog designer how much do you
use various mathematical concepts.

A lot of what I do is (a) for a given electro-optical design concept, calculate how good it _could_ be, (b) figure out how to get there, and (c) if that's a win, proceed, but if not, think up something better and goto(a)..

Significant amounts of math are required to get a good result, as well as a lot of lore and old fashioned crank-turning.

My favorite type of math is 'back of the envelope' calculations.
Those are fun... but it is always better with one or two other
people. (you can sorta check each other..)

George H.

Cheers

Phil Hobbs

We play a game, in a meeting, of doing the math in our heads. To
slide-rule sort of accuracy, not many digits, but close enough to see
what matters.

We've got pretty good at it, so we can really impress visitors.

Right... except in my game you're allowed an envelope (or bar
napkin) to scribble on... sometimes many bar napkins... depends
on the paper quality... and how good your pen is. :^)

It's mostly the spit balling of ideas.

George H.

--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[Joerg]

On 2020-03-28 15:19, Rick C wrote:

On Saturday, March 28, 2020 at 6:08:43 PM UTC-4, Joerg wrote:
On 2020-03-28 13:38, blocher@columbus.rr.com wrote:
On Friday, March 27, 2020 at 6:00:10 PM UTC-4, Rick C wrote:

[...]


So your work is not so much circuit design as it is system
design?

I like to think I straddle circuits and systems. I am decent at
both but certainly not an expert at analog. The problem in my
company is that there is not enough work in circuit design to
keep one always busy. I also think that most circuit problems
are better solved through a system approach. If you get the
system concept wrong, then the circuit is going to be wrong. If
you know what you want at the high level, it is easier to tell if
your circuit design is adequate.


Amen!

Top-down is generally the only approach that really works. Now
we'll have to explain that to the next generations. All the ones
who have served in the military don't need to be told, they know
this already.

There are very few times when a pure top down approach is used.

In medical and aerospace all the time. Has to be that way, else you can
land in hot water with the Federales. Without a top-down approach it is
hard to maintain a proper design history file set.

... Then
even when it is used that's only because the bottom portions are
very, very similar to something you've already completed.

It is seldom a design project is just pure design. There are almost
always questions near the bottom that can only be resolved by bottom
up design for at least that portion.

One thing that bottom up design does is to make testing easier. When
people talk about top down design they usually really mean top down
decomposition and bottom up design.

My projects typically start at the system spec level. That gets drilled
into and sub-projects are parceled out. That way the documentation is
always first and will be fleshed further out during the design. Not as
an afterthought like it unfortunately is with many others.

--
Regards, Joerg

http://www.analogconsultants.com/