Where have all the analogue men gone?

Richard Owlett wrote:

> Jerry Avins wrote:
> 
>> Richard Owlett wrote:
>>
>>> Jerry Avins wrote:
>>>
>>>>  
>>>> I had exactly one college course in digital electronics. (I learned, 
>>>> among other circuits, about phantastrons.*)
>>>
>>>
>>>
>>>
>>> What! No magnetic amplifiers?
>>> I've some of my father's appnotes [somewhere] from your era.
>>> P.S. He also operated a spark-gap transmitter at one time.
>>>
>>>>
>>>> Trick question: which is stronger; white oak or white pine?
>>>
>>>
>>>
>>>
>>> OK, I'll bite. What's the trick?
>>
>>
>>
>> Any wood worker will tell you that oak is stronger. What circumstances
>> make his answer wrong? (Hint: pine makes a better mast than oak.)
>>
>> Jerry
> 
> 
> Hmmm
> Would I be close saying it was similar to concrete vs steel
> 
> ie
> concrete:oak::steel:pine

Not as I see it. Concrete and steel are basically different materials.
Cellulose has the same strength no matter what tree it grows in.
Strength is a matter of how much there is, i.e., density. Oak is
stronger for the same size. Short oak and pine columns of the same
weight can bear the same load. Pine columns, whose larger diameter more
than offsets their lower elastic modulus, can be taller before they
buckle. Likewise, a pine beam geometrically similar to an oak beam of
the same weight can carry greater weight for the same span. Balsa wood
could carry more yet if bending were the only consideration.

Lateral forces resisted by stays put a mast in compression, sometimes
nearly to the Euler (buckling) limit. Lateral forces on sections of a
mast not directly resisted by stays exert bending moments on a mast. A
boat's stability is adversely affected by weight aloft. So ...

Jerry
-- 
... the worst possible design that just meets the specification - almost
a definition of practical engineering.                     .. Chris Bore
������������������������������������������������������������������������

Jerry Avins <jya@ieee.org> wrote in message news:<4124fad9$0$21762$61fed72c@news.rcn.com>...
>> Not as I see it. Concrete and steel are basically different materials.
> Cellulose has the same strength no matter what tree it grows in.
> Strength is a matter of how much there is, i.e., density. Oak is
> stronger for the same size. Short oak and pine columns of the same
> weight can bear the same load. Pine columns, whose larger diameter more
> than offsets their lower elastic modulus, can be taller before they
> buckle. Likewise, a pine beam geometrically similar to an oak beam of
> the same weight can carry greater weight for the same span. Balsa wood
> could carry more yet if bending were the only consideration.
> 
> Lateral forces resisted by stays put a mast in compression, sometimes
> nearly to the Euler (buckling) limit. Lateral forces on sections of a
> mast not directly resisted by stays exert bending moments on a mast. A
> boat's stability is adversely affected by weight aloft. So ...

...balsa is the ideal material for making masts?

Rune

Rune Allnor wrote:

   ...

> ...balsa is the ideal material for making masts?

No. Not enough tensile or compressive strength across the grain to 
permit sensible fastenings; too much wasted room on deck to accommodate 
the necessary diameter; etc.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

"Tim Wescott" <tim@wescottnospamdesign.com> wrote in message
news:10i2vd45ce45t0c@corp.supernews.com...
> Universities are subject to fads; they've been discouraging folk from
> learning analog for at least 20 years to my knowledge.

Worse, they're subject to funding from companies who want them to train
their future employees.

My best friend during high school got his electrical engineering degree from
MIT in 1968. He tells me that analog technology had been had been replaced
in most textbooks with logic gates by the late '50s. A late 1940s EE
textbook contains a wealth of knowledge that older folks took so for granted
that little was ever published outside of text books. The younger folks have
never been taught most of it so the wheel keeps getting reinvented.

-- 
Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!
615.385.8051    http://www.hyperback.com

In article <NZm_c.306487$OB3.200247@bgtnsc05-news.ops.worldnet.att.net>,
Bob Olhsson <olh@hyperback.com> wrote:
>My best friend during high school got his electrical engineering
>degree from MIT in 1968. He tells me that analog technology had
>been had been replaced in most textbooks with logic gates by the
>late '50s. A late 1940s EE textbook contains a wealth of knowledge
>that older folks took so for granted that little was ever published
>outside of text books.

This reminds me of a fascinating incident that occurred during
a previous employment with the Dept of Defense, revealing the
divergence of direction in electronics expertise between the United
States and Soviet Union during the Cold War.

A certain anti-ship missile that didn't go off, was dredged up by
our forces and sent to the lab where I worked, for the purpose of
figuring out the workings of the missile's seeker.  If you know
the details of a seeker's waveforms, thresholds, tracking logic,
decoy rejection logic, flight control logic, etc., you can devise
countermeasures against that missile, which is understandably of
great interest to the military.

Now, the U.S. considered this missile to be pretty sophisticated
for its time (early 1990s).  Disassembly revealed that the seeker
electronics consisted solely of (drum roll) analog electronics.
Made up of discrete components, no less.  Essentially, an analog
computer.

The Eastern Bloc, apparently, had made little or no progress in the
field of computing and digital electronics, concentrating instead
on developing expertise in analog technology to a degree unheard
of in the history of the United States.  This thing consisted of a
bewildering yet elegant and complex network of amplifiers, feedback
loops, adaptive analog filters, and so forth.  It was a brilliant
piece of work, roundly admired by all the scientists and engineers
who attempted to understand it, for they could not conceive of
anyone tackling the task of building a sophisticated missile seeker
that way.  Even the oldest graybeards among them were amazed.

If analog technology is all but dead here, I am sure it's still
alive and healthy there, even now, because the generation who built
such things are still alive and working today.

-A

axlq@spamcop.net (axlq) wrote in message news:<chd3c2$1l2$1@blue.rahul.net>...
> In article <NZm_c.306487$OB3.200247@bgtnsc05-news.ops.worldnet.att.net>,
> Bob Olhsson <olh@hyperback.com> wrote:
> >My best friend during high school got his electrical engineering
> >degree from MIT in 1968. He tells me that analog technology had
> >been had been replaced in most textbooks with logic gates by the
> >late '50s. A late 1940s EE textbook contains a wealth of knowledge
> >that older folks took so for granted that little was ever published
> >outside of text books.
> 
> This reminds me of a fascinating incident that occurred during
> a previous employment with the Dept of Defense, revealing the
> divergence of direction in electronics expertise between the United
> States and Soviet Union during the Cold War.
> 
> A certain anti-ship missile that didn't go off, was dredged up by
> our forces and sent to the lab where I worked, for the purpose of
> figuring out the workings of the missile's seeker.  If you know
> the details of a seeker's waveforms, thresholds, tracking logic,
> decoy rejection logic, flight control logic, etc., you can devise
> countermeasures against that missile, which is understandably of
> great interest to the military.
> 
> Now, the U.S. considered this missile to be pretty sophisticated
> for its time (early 1990s).  Disassembly revealed that the seeker
> electronics consisted solely of (drum roll) analog electronics.
> Made up of discrete components, no less.  Essentially, an analog
> computer.
> 
> The Eastern Bloc, apparently, had made little or no progress in the
> field of computing and digital electronics, concentrating instead
> on developing expertise in analog technology to a degree unheard
> of in the history of the United States.  This thing consisted of a
> bewildering yet elegant and complex network of amplifiers, feedback
> loops, adaptive analog filters, and so forth.  It was a brilliant
> piece of work, roundly admired by all the scientists and engineers
> who attempted to understand it, for they could not conceive of
> anyone tackling the task of building a sophisticated missile seeker
> that way.  Even the oldest graybeards among them were amazed.
> 
> If analog technology is all but dead here, I am sure it's still
> alive and healthy there, even now, because the generation who built
> such things are still alive and working today.
> 
> -A

I heard some rumours in the early nineties, that medical doctors from 
the eastern block were in great demand in the west, right after the 
iron curtain went down. The rationale was supposed to be that the 
easterners relied less on technology in their work, and somehow 
understood more of the interplay between injury and treatment, and could 
come up with a diagnosi and a treatment based on way fewer medical "data"
than their western collegues. I have no idea if that really was the 
case, though. 
 
The eastern philosophy of rugged, "simple" designs has its advantages.
A maintenance technician of the type of system you describe, could go 
to his local radio shack and get replacement parts. That would hardly 
be the case for his western counterpart. Eastern equipment kan take, 
and survive, abuses we consider ridicilous. Russian airplanes can 
apparently operate from muddy fields, where western airplanes get 
grounded by a few grains of sand in ther jet engines. I suspect the 
russians learned some lessons in 1941-42 that we here in the west have 
yet to comprehend the full implications of. 

It's like those high-tech assault rifles with laser aims and IR scopes. 
Run out of batteries, and they are worth little more than a stone-age club. 

Rune

"axlq" <axlq@spamcop.net> wrote in message
news:chd3c2$1l2$1@blue.rahul.net...
> The Eastern Bloc, apparently, had made little or no progress in the
> field of computing and digital electronics, concentrating instead
> on developing expertise in analog technology to a degree unheard
> of in the history of the United States.

It isn't that they'd made little or no progress, it was that it would have
made them too dependent on using Western Bloc parts to do it economically.
My understanding is that analog technology has moved ahead just as fast as
digital and many commonly cited shortcomings of analog were actually
overcome years ago. There's engineering and then there's the stock market.

-- 
Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!
615.385.8051    http://www.hyperback.com

In article <R73%c.560443$Gx4.255102@bgtnsc04-news.ops.worldnet.att.net>,
Bob Olhsson <olh@hyperback.com> wrote:
>"axlq" <axlq@spamcop.net> wrote in message
>news:chd3c2$1l2$1@blue.rahul.net...
>> The Eastern Bloc, apparently, had made little or no progress in the
>> field of computing and digital electronics, concentrating instead
>> on developing expertise in analog technology to a degree unheard
>> of in the history of the United States.
>
>It isn't that they'd made little or no progress, it was that it would have
>made them too dependent on using Western Bloc parts to do it economically.

Well, that's really the same as saying they made little or no
progress.  As you suggest, this lack of progress was likely their
choice, and not due to a lack of expertise.

>My understanding is that analog technology has moved ahead just as fast as
>digital and many commonly cited shortcomings of analog were actually
>overcome years ago. There's engineering and then there's the stock market.

Hmmm... that is to say, when you have no stock market, you have
better engineering?  I can't buy that, but I will agree that it may
have been a factor in their developing analog technology further
than we would dream of here.

-Alex

Jerry Avins wrote:

> Tom wrote:
> 
>> "Jerry Avins" <jya@ieee.org> wrote in message
>> news:4122262b$0$5904$61fed72c@news.rcn.com...
>> 
>>>Tie the output of a CMOS
>>>inverter back to its input with a 100K resistor, capacitively
>>>couple a signal to the input, and you have a dandy 20 dB audio
>>>amplifier.
>> 
>> 
>> I think I have seen this somewhere before. I assume the output
>> swings about Vcc/2 does it?
>> How good is this sort of amplifier,distortion etc.
>> 
>> Tom
> 
> With a series resistor on the input also, feedback makes the
> output very linear. The intrinsic gain is only between 10 and 30,
> so reducing it with feedback doesn't leave much. Cascading three
> CD4049s, feeding back with a 1 meg resistor, and using a 10 K
> resistor in the input (a 1 muF capacitor gets you down to 16 Hz)
> makes a dandy 40 dB mike amplifier.
> 
> Jerry

Some twenty years ago, I used 7400 TTL ICs to amplify.
I didn't realize that this works well with CMOS too, would have 
expected too bad SNR. I'll keep it in my mind, since I don't have a 
lot of TTL 7400s left in my drawer...

Bernhard

Tom wrote:

> It appears that a good analogue design engineer who can design at
> IC level even can demand a hugh salary - as digital guys are ten a
> penny. (I don't mean DSP but hardware digital). The higher the
> frequency the more challenging will be the ADC conversion process
> for instance.Do they still teach analogue at a high level at
> Universities? Why the shortage? I expect in an ideal world we
> would want the whole world to be digital so we can use CMOS and
> make it cheap as hell but life just isn't like that.
> 
> 
> Tom

My first impressive experience with analogue realm was during a 
thunderstorm, when the lightning rod of our house was struck by a 
lightning: the earth around the location where it used to be 
buried, had been exploded/vanished, leaving a crater and the rod 
directing into the air instead of into the ground. 
Only a smoky trace along the wall indicated that it was really work 
of nature and not a bad joke of the gang of neighbour kids...
I was amazed by this power.

Later when playing with a transformator, trying to connect it vice 
versa to generate my private lightning, I got my first stroke 
because I happened to touch the wrong pole... I looked around, if 
this was my father slapping me, but he wasn't there.
Again, I realized the amazing power of electricity.

It was quite obvious that I would discover more of this fascinating 
world of analog electronics. When I bought my first diodes and 
transistors in the late 60's and early 70's, digital electonic 
parts were not available - at first, because nobody sold them 
(nearby), later because they were too expensive. I had to go with 
discrete analog electronics.

Nevertheless, I was always excited in pioneering unexplored areas.
I realize that this is the same with my kids.
Only, that all areas of analog and digital electronics have been 
vastly explored, so that they can hardly find corners where they 
can pioneer. Computers and mobiles, right. But that's not really 
satisfying them. Creating computer viruses, worms, etc. has more 
potential. It's a pity that it drifts into the illegal area.


I guess that all starts in our childhood. There's a generation which 
had been raised during the age of analog electronics, when 
transistors and primitive analog ICs had been 
discovered/engineered. 
The kids of that age had strong interest in that stuff and therefore 
decided to work in that area.
Then this age was gone, replaced by the age of digital electronics 
and computers. And gone was the generation of analogue engineers, 
though with a shift of a couple of decades.

If somebody has the potential to be a good analogue engineer, is 
rooted in his/her childhood - my guess is that all those which have 
not this sort of background, cannot become good analogue designers.

I agree, that this becomes a problem, because frequencies go far 
beyond the GHz range, and analogue (especially HF) design aspects 
gain more and more importance.

If I am right, this will be an interesting challenge for the 
gray-haired (I start to belong to them ...).
Since they cannot be replaced, they will have important work until 
they retire, and beyond...

Bernhard