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Next: Any insight for Automotive Sensor Inputs/ Front-End Protection.
From: JosephKK on 30 Apr 2010 06:56
On Tue, 27 Apr 2010 18:36:27 +0800, "Royston Vasey" <royston(a)vasey.com>
wrote:

>
>"Charlie E." <edmondson(a)ieee.org> wrote in message
>news:kvkct5ttueknpcqgohje2n3d8pe4j7b7p9(a)4ax.com...
>> On Mon, 26 Apr 2010 19:16:48 -0700 (PDT), mpm <mpmillard(a)aol.com>
>> wrote:
>>
>>>On Apr 26, 8:11 pm, Charlie E. <edmond...(a)ieee.org> wrote:
>>>> On Mon, 26 Apr 2010 17:33:32 -0700 (PDT), mpm <mpmill...(a)aol.com>
>>>> wrote:
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> >On Apr 26, 5:07 pm, Charlie E. <edmond...(a)ieee.org> wrote:
>>>> >> Hi All,
>>>> >> You have given me good advice in the past, and I am now really close
>>>> >> to shipping this thing, but still running into some of the same old
>>>> >> problems.
>>>>
>>>> >> Basically, when I program a unit, it works great here on the bench,
>>>> >> and around the house, but when I go out into the real world, all heck
>>>> >> breaks loose!
>>>>
>>>> >> My present problems seem to revolve around dark colors. Browns shift
>>>> >> to dark red, or green, blacks suddenly become dark greens, dark
>>>> >> denims
>>>> >> become black, dark green, or even dark blue-green.
>>>>
>>>> >> Trying to determine the cause is difficult, because the problems
>>>> >> never
>>>> >> happen in the lab when I am in debug, and can get full data on what
>>>> >> is
>>>> >> going on internally. My present guesses all point to shifts in the
>>>> >> strengths of the LEDs and other electronics, perhaps with
>>>> >> temperature,
>>>> >> or maybe with differences in background lighting leaking into the
>>>> >> unit.
>>>>
>>>> >> So, can anyone offer any suggestions? You can find a schematic and a
>>>> >> photo of the unit
>>>> >> athttp://edmondsonengineering.com/RainbowColorReader.aspx
>>>>
>>>> >> Thanks in advance!
>>>>
>>>> >> Charlie
>>>>
>>>> >Hey Charlie,
>>>> >Can't help with your circuit, but it looks like a pretty cool device.
>>>> >It's the sort of thing that someone probably would never think of
>>>> >unless they were familiar with blindness.?
>>>> >I wonder if it could have application in teaching kids their colors,
>>>> >or for use with colorblind individual.
>>>> >Maybe an advanced unit to detect world currencies...??
>>>>
>>>> >My only thought is that maybe light is bouncing around in weird ways
>>>> >on the input.
>>>> >Try setting up some lights on your bench and see if you can emulate.
>>>> >Use different types of lights (flourescent, tungsten, basically, every
>>>> >wavelength you can think of).
>>>> >I would also experiment with different daylight times (outdoors, of
>>>> >course), as the Sunlight temperture varies considerably dusk to dawn.
>>>> >(You probably already know all this, right??!) Disclaimer: Amateur
>>>> >photographer here.
>>>>
>>>> >I notice you're in the United States.
>>>> >I thought I should point out a potential regulatory concern that
>>>> >involves offering products for sale before they have either been FCC-
>>>> >certified, or before the manufacturer (you!) has filed a Declaration
>>>> >of Confirmity.
>>>> >Honestly, I'm not sure which one your product would involve. Probably
>>>> >a DoC, but I don't know if they consider the LED emissions to require
>>>> >certification...?? Maybe someone here will know.
>>>> >Your PIC certainly operates fast enough to qualify for testing. I
>>>> >recall anything over 9kHz requires testing, though I could be wrong
>>>> >about that lower bound.
>>>> >8 to 32 MHz definitely qualifies, however.
>>>>
>>>> >I think the FCC might interpret your website as advertising of the
>>>> >product, particularly in light of your web text suggesting wholesale
>>>> >pricing. (I realize the product is not ready for sale, but that's not
>>>> >really the point.)
>>>> >If the FCC were to draw that conclusion, it could subject you to an
>>>> >Official Citation or Notice of Apparent Liability. The former is a
>>>> >slap on the wrist involving no out-of-poekct money. The latter can
>>>> >lead to possible fines and in-rem forfeiture - (though all of these
>>>> >outcomes are highly unlikely).
>>>>
>>>> >Either way, a quick review of the Rule may put your mind at ease. The
>>>> >Rule is FCC 2.803
>>>> >For convenience, here's the link:
>>>> >http://www.gpo.gov/fdsys/pkg/CFR-2009-title47-vol1/pdf/CFR-2009-title...
>>>>
>>>> >Not knowing your situation, my recommendation is to be safe just add
>>>> >the following text to your web site (the page that has pricing info):
>>>>
>>>> >This device has not been authorized as required
>>>> >by the rules of the Federal Communications
>>>> >Commission. This device is not,
>>>> >and may not be, offered for sale or lease, or
>>>> >sold or leased, until authorization is obtained.
>>>>
>>>> >The above is the exact language specified by 47CFR2.803(c).
>>>>
>>>> >Enjoy!! And best of luck with the project/product.
>>>> >-mpm
>>>>
>>>> Hmmmm...
>>>> It is definitely not an intentional radiator, and no clock outputs
>>>> leave the chip. The two switchers are only going to a cap less than
>>>> 10 mm from the chip. Would never have thought anything this simple
>>>> could need certification. Jeorge? Any thoughts?
>>>>
>>>> Thanks,
>>>> Charlie- Hide quoted text -
>>>>
>>>> - Show quoted text -
>>>
>>>I wasn't too sure about whether the LED's were modulated, and if so,
>>>at what frequency, etc..,
>>>
>>>Your device appears to be in the same family tree as small battery-
>>>powered calculators and TV remotes.
>>>In other words, a Class-B (household) digital device, configured as an
>>>unintentional radiator
>>>Note: A digital device is pretty much anything with a clock faster
>>>than 9 kHz.
>>>
>>>Typically, these types of devices will have DoC's, and I suspect yours
>>>should as well.
>>>That said, the rules appear vague and flexible enough to allow
>>>Verification.
>>>
>>>See FCC Rule 15.101. Link:
>>>http://www.gpo.gov/fdsys/pkg/CFR-2009-title47-vol1/pdf/CFR-2009-title47-vol1-part15.pdf
>>>
>>>Sorry to rain on your parade, (if I have?). Just thought you should
>>>be aware, particularly given the advertising thing.
>>>The good news is that Verification / DoC is a lot cheaper, easier and
>>>faster to get than a full-blown TCB Equipment Certification.
>>>
>>>Again, best of luck getting the bugs out!
>>>-mpm
>>>
>>>
>>>
>>
>> Ok, heart attack over. From the FCC at
>> http://www.fcc.gov/oet/ea/ea_app_info.html
>>
>> looks like we don't even have to file anything, just put a note in our
>> instructions that we meet (verification) the specs. Whewwww... you
>> had me worried there!
>>
>> Charlie
>
>
>I'm in another country Charlie, but have had similar compliance issues with
>low volume items. If you feel the need, find a friendly EMC test lab and see
>if he will rent himself to you for a couple of hours & provide you with a
>couple of spectrograms to show that emissions are acceptable. The cost goes
>up up up if the lab writes up any report for you.
>
Doing so would go a long ways in demonstrating due diligence. Test as
many units as you can afford and document them all.
From: JosephKK on 30 Apr 2010 07:06
On Wed, 28 Apr 2010 16:10:16 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote:

>On Wed, 28 Apr 2010 14:41:53 -0700, Jon Kirwan
><jonk(a)infinitefactors.org> wrote:
>
>>On Mon, 26 Apr 2010 15:07:02 -0700, Charlie E.
>><edmondson(a)ieee.org> wrote:
>>
>>><snip>
>>>So, can anyone offer any suggestions? You can find a schematic and a
>>>photo of the unit at
>>>http://edmondsonengineering.com/RainbowColorReader.aspx
>>
>>I did offer a thought, earlier. No response to it.
>>
>>Have you read and do you fully understand the CIE 1931 and
>>1964 color standards? (If you are really into this, I'd also
>>recommend Edwin Land's work papers from the late 1970's to
>>early 1980's -- you may not need to, but it is just very
>>interesting to study and it addresses directly some points
>>that relate squarely on various lighting situations as you
>>are encountering.)
>>
>>>My present problems seem to revolve around dark colors. Browns shift
>>>to dark red, or green, blacks suddenly become dark greens, dark denims
>>>become black, dark green, or even dark blue-green.
>>
>>Which is exactly the area that Edwin Land highlights in his
>>research reports...
>>
>>In other words, how much do you understand about human color
>>perception?
>>
>>By the way, what are you using as your comparison "standard?"
>>Your eye? Or?
>>
>>Jon
>
>No need to get snotty. The question on the floor is _electronic_, lab
>versus _field_.
>
> ...Jim Thompson

While i did not read Jon's post as snotty, i can see how it can be read
that way. It struck me more as a "did you know of this(?), which seems
like it would be helpful".
From: Jon Kirwan on 2 May 2010 14:34
On Fri, 30 Apr 2010 04:06:13 -0700,
"JosephKK"<quiettechblue(a)yahoo.com> wrote:

>On Wed, 28 Apr 2010 16:10:16 -0700, Jim Thompson
><To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote:
>
>>On Wed, 28 Apr 2010 14:41:53 -0700, Jon Kirwan
>><jonk(a)infinitefactors.org> wrote:
>>
>>>On Mon, 26 Apr 2010 15:07:02 -0700, Charlie E.
>>><edmondson(a)ieee.org> wrote:
>>>
>>>><snip>
>>>>So, can anyone offer any suggestions? You can find a schematic and a
>>>>photo of the unit at
>>>>http://edmondsonengineering.com/RainbowColorReader.aspx
>>>
>>>I did offer a thought, earlier. No response to it.
>>>
>>>Have you read and do you fully understand the CIE 1931 and
>>>1964 color standards? (If you are really into this, I'd also
>>>recommend Edwin Land's work papers from the late 1970's to
>>>early 1980's -- you may not need to, but it is just very
>>>interesting to study and it addresses directly some points
>>>that relate squarely on various lighting situations as you
>>>are encountering.)
>>>
>>>>My present problems seem to revolve around dark colors. Browns shift
>>>>to dark red, or green, blacks suddenly become dark greens, dark denims
>>>>become black, dark green, or even dark blue-green.
>>>
>>>Which is exactly the area that Edwin Land highlights in his
>>>research reports...
>>>
>>>In other words, how much do you understand about human color
>>>perception?
>>>
>>>By the way, what are you using as your comparison "standard?"
>>>Your eye? Or?
>>>
>>>Jon
>>
>>No need to get snotty. The question on the floor is _electronic_, lab
>>versus _field_.
>>
>> ...Jim Thompson
>
>While i did not read Jon's post as snotty, i can see how it can be read
>that way. It struck me more as a "did you know of this(?), which seems
>like it would be helpful".

Thanks. It was offered in that vein.

The funding of accurate human color perception _measurement_
dates back at least to the time when colored house paints
began to be sold (by Sears, for example) as something to
'spruce up' homes. (Turn of 19th to 20th century, roughly.)

Customers would buy a 'brown' for an addition, hoping to get
the same 'brown' they ordered two years before, and getting
something that 'any idiot' could see wasn't even close. The
control of paint chemicals and dyes wasn't sufficient by
itself at the time and there was a strong need for some
"feedback" to help adjust the dyes, as appropriate.

This commercial desire played into a university research
desire regarding color blindness and provided a substantial
funding source for this research to proceed.

A method was needed so that a 'brown' paint bought today and
used on the shady part of a home would look the same as the
same 'brown' paint bought next year and used on a well-lit
side. Side by side, the two paint jobs should "look the
same" to a viewer -- VERY WIDELY varying lighting conditions.

The CIE color system has remarkable fidelity for that
purpose. It also can deal with lighting conditions within
some limits.

What it does not do is cope with the surroundings, which in
human perception is very important. That is one reason why I
pointed him at Edwin Land and one reason why I wondered how
Charlie was determining when the color reading was wrong or
right.

If you take a canvas and place it on a painting easel and put
swatches of colors nearby each other on that canvas and light
it with a bright 100W tungsten bulb, people will see the
colors a certain way. Then, as you dim the bulb down, the
Planck radiation curve emitted will shift dramatically in
wavelength -- all of us here are well aware of this fact --
causing reflections and the resulting distribution of
wavelengths from the surfaces to be markedly different than
before. Yet even operating at 10W or even 1W of output, with
the distribution almost totally different than before, a
human will still "see" the same "colors."

Do the same experiment, now instead with a cover sheet that
blocks out all but one selected color swatch and the human
will NO LONGER see the same colors when the lighting is
changed. This proved that the human vision system uses the
reflections from nearby areas to help adduce any nearby
color. As the reflections shift dramatically for one color
swatch, so it also shifts for others nearby. Lose that
additional information source and the brain can't maintain
the perception. Keep it, and it can.

Edwin Land spent years studying this phenomenon well after
both CIE standards groups put out their results and it turns
out that humans also use nearby colors to "calibrate" their
perceptions.

In any case, it is VERY illuminating to study this material
(the CIE _and_ Dr. Land research papers) and it _may_ bear on
this "issue." It made sense to me to at least ask if the OP
is fully familiar with the existing research here.

I spent some years working with OSRAM on these issues. I
worried that Charlie may be fighting an issue that might be
more easily 'understood' from a different domain. He is in a
better position to generally know one way or another, but a
small pointer might help if he wasn't already aware.

Jon
From: Charlie E. on 2 May 2010 20:43
On Sun, 02 May 2010 11:34:58 -0700, Jon Kirwan
<jonk(a)infinitefactors.org> wrote:

>On Fri, 30 Apr 2010 04:06:13 -0700,
>"JosephKK"<quiettechblue(a)yahoo.com> wrote:
>
>>On Wed, 28 Apr 2010 16:10:16 -0700, Jim Thompson
>><To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote:
>>
>>>On Wed, 28 Apr 2010 14:41:53 -0700, Jon Kirwan
>>><jonk(a)infinitefactors.org> wrote:
>>>
>>>>On Mon, 26 Apr 2010 15:07:02 -0700, Charlie E.
>>>><edmondson(a)ieee.org> wrote:
>>>>
>>>>><snip>
>>>>>So, can anyone offer any suggestions? You can find a schematic and a
>>>>>photo of the unit at
>>>>>http://edmondsonengineering.com/RainbowColorReader.aspx
>>>>
>>>>I did offer a thought, earlier. No response to it.
>>>>
>>>>Have you read and do you fully understand the CIE 1931 and
>>>>1964 color standards? (If you are really into this, I'd also
>>>>recommend Edwin Land's work papers from the late 1970's to
>>>>early 1980's -- you may not need to, but it is just very
>>>>interesting to study and it addresses directly some points
>>>>that relate squarely on various lighting situations as you
>>>>are encountering.)
>>>>
>>>>>My present problems seem to revolve around dark colors. Browns shift
>>>>>to dark red, or green, blacks suddenly become dark greens, dark denims
>>>>>become black, dark green, or even dark blue-green.
>>>>
>>>>Which is exactly the area that Edwin Land highlights in his
>>>>research reports...
>>>>
>>>>In other words, how much do you understand about human color
>>>>perception?
>>>>
>>>>By the way, what are you using as your comparison "standard?"
>>>>Your eye? Or?
>>>>
>>>>Jon
>>>
>>>No need to get snotty. The question on the floor is _electronic_, lab
>>>versus _field_.
>>>
>>> ...Jim Thompson
>>
>>While i did not read Jon's post as snotty, i can see how it can be read
>>that way. It struck me more as a "did you know of this(?), which seems
>>like it would be helpful".
>
>Thanks. It was offered in that vein.
>
>The funding of accurate human color perception _measurement_
>dates back at least to the time when colored house paints
>began to be sold (by Sears, for example) as something to
>'spruce up' homes. (Turn of 19th to 20th century, roughly.)
>
>Customers would buy a 'brown' for an addition, hoping to get
>the same 'brown' they ordered two years before, and getting
>something that 'any idiot' could see wasn't even close. The
>control of paint chemicals and dyes wasn't sufficient by
>itself at the time and there was a strong need for some
>"feedback" to help adjust the dyes, as appropriate.
>
>This commercial desire played into a university research
>desire regarding color blindness and provided a substantial
>funding source for this research to proceed.
>
>A method was needed so that a 'brown' paint bought today and
>used on the shady part of a home would look the same as the
>same 'brown' paint bought next year and used on a well-lit
>side. Side by side, the two paint jobs should "look the
>same" to a viewer -- VERY WIDELY varying lighting conditions.
>
>The CIE color system has remarkable fidelity for that
>purpose. It also can deal with lighting conditions within
>some limits.
>
>What it does not do is cope with the surroundings, which in
>human perception is very important. That is one reason why I
>pointed him at Edwin Land and one reason why I wondered how
>Charlie was determining when the color reading was wrong or
>right.
>
>If you take a canvas and place it on a painting easel and put
>swatches of colors nearby each other on that canvas and light
>it with a bright 100W tungsten bulb, people will see the
>colors a certain way. Then, as you dim the bulb down, the
>Planck radiation curve emitted will shift dramatically in
>wavelength -- all of us here are well aware of this fact --
>causing reflections and the resulting distribution of
>wavelengths from the surfaces to be markedly different than
>before. Yet even operating at 10W or even 1W of output, with
>the distribution almost totally different than before, a
>human will still "see" the same "colors."
>
>Do the same experiment, now instead with a cover sheet that
>blocks out all but one selected color swatch and the human
>will NO LONGER see the same colors when the lighting is
>changed. This proved that the human vision system uses the
>reflections from nearby areas to help adduce any nearby
>color. As the reflections shift dramatically for one color
>swatch, so it also shifts for others nearby. Lose that
>additional information source and the brain can't maintain
>the perception. Keep it, and it can.
>
>Edwin Land spent years studying this phenomenon well after
>both CIE standards groups put out their results and it turns
>out that humans also use nearby colors to "calibrate" their
>perceptions.
>
>In any case, it is VERY illuminating to study this material
>(the CIE _and_ Dr. Land research papers) and it _may_ bear on
>this "issue." It made sense to me to at least ask if the OP
>is fully familiar with the existing research here.
>
>I spent some years working with OSRAM on these issues. I
>worried that Charlie may be fighting an issue that might be
>more easily 'understood' from a different domain. He is in a
>better position to generally know one way or another, but a
>small pointer might help if he wasn't already aware.
>
>Jon

Hi Jon,
Basically, yes, I am using my own eyes as a calibration source, sort
of...

Since I have chosen my illumination source, and RGB LED run one color
at a time, I am not dealing with different illumination sources. I am
also not trying to do high accuracy color determination, just red,
green, blue, orange, etc. My frustration is that two units,
apparently calibrated identically, will still see certain colors
differently. Trying to identify the source of the differences led me
to consult with my friends here to see if there was some electronic
design error on my part. I suspect that, such little things as
different alignments of the LED and PT, different arrangements of my
blocking black felt, and even temperature of the unit may be enough to
skew the results so that certain 'border' colors change nations, i.e
beige becomes pink, gold becomes orange, and blue becomes purple, or
blue green.

Fortunately, in my market, it appears that this is a conundrum that
hasn't really been solved yet! Some makers require a calibration
before every read. I think I may just ship what I have, and see if it
is useful enough at my price point, to make sales.

Charlie
From: Sjouke Burry on 2 May 2010 21:15
Charlie E. wrote:
> On Sun, 02 May 2010 11:34:58 -0700, Jon Kirwan
> <jonk(a)infinitefactors.org> wrote:
>
>> On Fri, 30 Apr 2010 04:06:13 -0700,
>> "JosephKK"<quiettechblue(a)yahoo.com> wrote:
>>
>>> On Wed, 28 Apr 2010 16:10:16 -0700, Jim Thompson
>>> <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote:
>>>
>>>> On Wed, 28 Apr 2010 14:41:53 -0700, Jon Kirwan
>>>> <jonk(a)infinitefactors.org> wrote:
>>>>
>>>>> On Mon, 26 Apr 2010 15:07:02 -0700, Charlie E.
>>>>> <edmondson(a)ieee.org> wrote:
>>>>>
>>>>>> <snip>
>>>>>> So, can anyone offer any suggestions? You can find a schematic and a
>>>>>> photo of the unit at
cut
> Basically, yes, I am using my own eyes as a calibration source, sort
> of...
>
> Since I have chosen my
Cut
Your eye's may be quite insufficient.
I compared some time ago with a college, we both had correct
color vision(according to some standard tests).
Then we used a little test device, with one halve circle true yellow
and another half circle you could adjust red and green to get the same
hue and intensity yellow.
Well.... My yellow was pale green-yellow according to my college,
and his yellow looked to me like orange.
So when you fiddle around with an rgb led, your eyesight is a
poor judge, and some hardware to test would be better.
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Prev: Financial Management Theory & Practice by Eugene F. Brigham, Michael C. Ehrhardt 13th Edition 2011 Solution manual is available for purchase at affordable prices. Contact me at alltestbanks11[at]gmail.com to buy it today. All emails will be answer
Next: Any insight for Automotive Sensor Inputs/ Front-End Protection.