Conical inductors--still $10!...

[Ricketty C]

On Wednesday, July 15, 2020 at 4:17:03 PM UTC-4, edward...@gmail.com wrote:

On Wednesday, July 15, 2020 at 12:47:37 PM UTC-7, Ricketty C wrote:
On Wednesday, July 15, 2020 at 12:47:46 PM UTC-4, edward...@gmail.com wrote:
Just like with Tesla stock at 1500 I won\'t buy it and I won\'t go short either,

Yes, they need to shut down Fremont factory immediately:

https://sanfrancisco.cbslocal.com/2020/07/14/coronavirus-tesla-workers-speak-out-after-industry-blog-reports-dozens-of-workers-tested-positive-for-covid-19/

From time to time I post in a Tesla forum, but it is actually a more hostile environment than this group if you can believe that... well, it is if you are not a fanboi of Tesla. I try to be even handed and much like here, when people disagree with me, I often learn something.

They defied Alameda County order to shutdown before, now there are more than 100 positive cases. State and County officials just ignored it. I guess \"Money before Life\".

It will be interesting to see if the scheduled factory closing later this month has an impact. I would not expect it given a factory of what, 10,000 people in a county of 1.6 million. Too many other impacts.

Other than the peninsula, everywhere around the bay area is really spiking from the pandemic. You can expect to see higher death rates around the end of the month or early August, Tesla Fremont open or not.

It\'s going to get ugly around the bay area soon.

--

Rick C.

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

 

[Ricketty C]

On Wednesday, July 15, 2020 at 4:17:03 PM UTC-4, edward...@gmail.com wrote:

On Wednesday, July 15, 2020 at 12:47:37 PM UTC-7, Ricketty C wrote:
On Wednesday, July 15, 2020 at 12:47:46 PM UTC-4, edward...@gmail.com wrote:
Just like with Tesla stock at 1500 I won\'t buy it and I won\'t go short either,

Yes, they need to shut down Fremont factory immediately:

https://sanfrancisco.cbslocal.com/2020/07/14/coronavirus-tesla-workers-speak-out-after-industry-blog-reports-dozens-of-workers-tested-positive-for-covid-19/

From time to time I post in a Tesla forum, but it is actually a more hostile environment than this group if you can believe that... well, it is if you are not a fanboi of Tesla. I try to be even handed and much like here, when people disagree with me, I often learn something.

They defied Alameda County order to shutdown before, now there are more than 100 positive cases. State and County officials just ignored it. I guess \"Money before Life\".

It will be interesting to see if the scheduled factory closing later this month has an impact. I would not expect it given a factory of what, 10,000 people in a county of 1.6 million. Too many other impacts.

Other than the peninsula, everywhere around the bay area is really spiking from the pandemic. You can expect to see higher death rates around the end of the month or early August, Tesla Fremont open or not.

It\'s going to get ugly around the bay area soon.

--

Rick C.

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

 

[Ricketty C]

On Wednesday, July 15, 2020 at 4:19:31 PM UTC-4, Lasse Langwadt Christensen wrote:

onsdag den 15. juli 2020 kl. 21.55.04 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 2:13:16 PM UTC-4, Lasse Langwadt Christensen wrote:
onsdag den 15. juli 2020 kl. 20.04.55 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 12:47:46 PM UTC-4, Pimpom wrote:
On 7/15/2020 9:14 PM, Joe Gwinn wrote:
On 15 Jul 2020 14:32:46 GMT, Rob <nomail@example.com> wrote:

jlarkin@highlandsniptechnology.com <jlarkin@highlandsniptechnology.com> wrote:
One of my most common causes of writing ECOs against new designs is
that the LEDs are too bright. Gotta do that again today.

It is even more true for blue leds than for green. When a device
has a blue indicator LED, it usually is far too bright. Both my PC
and my router have indicator lights that, when not taped over, cause
a large blue spot to appear on the opposite wall.

The best use of this I\'ve seen is Bosch dishwashers, the models that
have no visible controls or indicators when the door is closed:

They use a blue LED to project a spot on the floor - if the spot is
steady, the diswasher is happily progressing through its cycle. If
blinking, go figure out why.

I used a blue LED projection as an indicator in a custom-built
product I made last year. The central unit is housed in a white
plastic box which is completely closed except for an antenna and
a USB port. Going by a last minute inspiration, I projected the
blue LED at the inside of the box from about 2cm away instead of
having it poke through the wall. The result is a diffused circle
of blue light. The customer loved it. The LED current is 1.5mA.

I think I\'ve seen clock that show their LEDs through a white plastic case. Blue LEDs behind white are very attractive I think. I much prefer blue LEDs to red ones.


I\'m sure I\'ve seen some standard that specifies that red should be reserved for errors and warnings

You can find red LED clocks all over the place. I think that standard applies only to indicators intended to indicate status, not time keeping numeric LEDs.


maybe that is just a side effect of red being first led color and thus most commonly available?

Not sure what that means, \"most commonly available\". They make them in many colors, so obviously there\'s no shortage. I think they sell what people buy and mostly people buy on very frivolous matters when all else is equal. I bought a used alarm clock once because I couldn\'t find a decent blue one in the stores. lol $10 shipped. It was actually for a girlfriend to go next to her TV, but she moved and I ended up with it.

I would say most people just prefer the red in LED clocks.

--

Rick C.

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

 

[Ricketty C]

On Wednesday, July 15, 2020 at 4:19:31 PM UTC-4, Lasse Langwadt Christensen wrote:

onsdag den 15. juli 2020 kl. 21.55.04 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 2:13:16 PM UTC-4, Lasse Langwadt Christensen wrote:
onsdag den 15. juli 2020 kl. 20.04.55 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 12:47:46 PM UTC-4, Pimpom wrote:
On 7/15/2020 9:14 PM, Joe Gwinn wrote:
On 15 Jul 2020 14:32:46 GMT, Rob <nomail@example.com> wrote:

jlarkin@highlandsniptechnology.com <jlarkin@highlandsniptechnology.com> wrote:
One of my most common causes of writing ECOs against new designs is
that the LEDs are too bright. Gotta do that again today.

It is even more true for blue leds than for green. When a device
has a blue indicator LED, it usually is far too bright. Both my PC
and my router have indicator lights that, when not taped over, cause
a large blue spot to appear on the opposite wall.

The best use of this I\'ve seen is Bosch dishwashers, the models that
have no visible controls or indicators when the door is closed:

They use a blue LED to project a spot on the floor - if the spot is
steady, the diswasher is happily progressing through its cycle. If
blinking, go figure out why.

I used a blue LED projection as an indicator in a custom-built
product I made last year. The central unit is housed in a white
plastic box which is completely closed except for an antenna and
a USB port. Going by a last minute inspiration, I projected the
blue LED at the inside of the box from about 2cm away instead of
having it poke through the wall. The result is a diffused circle
of blue light. The customer loved it. The LED current is 1.5mA.

I think I\'ve seen clock that show their LEDs through a white plastic case. Blue LEDs behind white are very attractive I think. I much prefer blue LEDs to red ones.


I\'m sure I\'ve seen some standard that specifies that red should be reserved for errors and warnings

You can find red LED clocks all over the place. I think that standard applies only to indicators intended to indicate status, not time keeping numeric LEDs.


maybe that is just a side effect of red being first led color and thus most commonly available?

Not sure what that means, \"most commonly available\". They make them in many colors, so obviously there\'s no shortage. I think they sell what people buy and mostly people buy on very frivolous matters when all else is equal. I bought a used alarm clock once because I couldn\'t find a decent blue one in the stores. lol $10 shipped. It was actually for a girlfriend to go next to her TV, but she moved and I ended up with it.

I would say most people just prefer the red in LED clocks.

--

Rick C.

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

 

[Pimpom]

On 7/15/2020 1:18 PM, Ricketty C wrote:

On Wednesday, July 15, 2020 at 2:47:50 AM UTC-4, Pimpom wrote:
On 7/15/2020 10:06 AM, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU. However, I can\'t find a good chart of the I-V curve below 1 mA. The circuit supplies up to 1.15 mA which is measured by dropping it across a 1.5 k resistor yielding up to around 1.7 volts. This seems like it might be getting into a range where the LED might be stealing a significant portion of the current being measured. But none of the references I can find provide enough detail to know for sure. Most seem to be something along the lines of an \"artist\'s concept\" of a curve lying along the X axis until reaching some voltage where it takes off like a hockey stick. Others just seem to be a wag with only a very few points measured. None of them show any detail at the low end with 10 mA as the lowest line on the Y axis.

Anyone measured a green LED at low currents or know how they respond?

If needed, I can lower the resistor which will lower the voltage the LED will see, but I can\'t lower it too much or lose resolution of the measurement.

Maybe I should just give in and limit the voltage with a Zener diode. I was trying to keep a part off the BOM if possible. There\'s already a green LED in use.



I did a manual measurement of various no-name LEDs 10 years ago.
It included only one green 5mm LED. The current level probably
doesn\'t go as low as you want but FWIW this is what I got:

mA V

0.44 -- 2.608
0.5 --- 2.627
1 ----- 2.711
2 ----- 2.801
3 ----- 2.864
4 ----- 2.902
5 ----- 2.939
7 ----- 3.003
10 ---- 3.077
15.5 -- 3.141

Thanks for the data. That was just what I was looking for.

From that data it looks like it will have very minimal impact on the current over the voltage range of interest. But if I am using this to save adding a Zener diode but I have to have the part painted... doesn\'t seem worth the trouble. The case only has small air openings, but it has a large port on top covered by plexi so the workings can be monitored. So it will have indirect light inside the case falling on the LED. The case is stainless steel, so lots of reflection.

I wonder just how much the light will affect the LED. Low uA won\'t be a problem. 100\'s of uA will. Sounds like I should use the Zener.

I have no recorded data about the photoelectric effect but,
speaking from memory of a half-hearted test I once did, I can
assure you that it will not be hundreds of uA. I doubt that it
will even be in the \"low uA\" region under those conditions.

 

[Pimpom]

On 7/15/2020 1:18 PM, Ricketty C wrote:

On Wednesday, July 15, 2020 at 2:47:50 AM UTC-4, Pimpom wrote:
On 7/15/2020 10:06 AM, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU. However, I can\'t find a good chart of the I-V curve below 1 mA. The circuit supplies up to 1.15 mA which is measured by dropping it across a 1.5 k resistor yielding up to around 1.7 volts. This seems like it might be getting into a range where the LED might be stealing a significant portion of the current being measured. But none of the references I can find provide enough detail to know for sure. Most seem to be something along the lines of an \"artist\'s concept\" of a curve lying along the X axis until reaching some voltage where it takes off like a hockey stick. Others just seem to be a wag with only a very few points measured. None of them show any detail at the low end with 10 mA as the lowest line on the Y axis.

Anyone measured a green LED at low currents or know how they respond?

If needed, I can lower the resistor which will lower the voltage the LED will see, but I can\'t lower it too much or lose resolution of the measurement.

Maybe I should just give in and limit the voltage with a Zener diode. I was trying to keep a part off the BOM if possible. There\'s already a green LED in use.



I did a manual measurement of various no-name LEDs 10 years ago.
It included only one green 5mm LED. The current level probably
doesn\'t go as low as you want but FWIW this is what I got:

mA V

0.44 -- 2.608
0.5 --- 2.627
1 ----- 2.711
2 ----- 2.801
3 ----- 2.864
4 ----- 2.902
5 ----- 2.939
7 ----- 3.003
10 ---- 3.077
15.5 -- 3.141

Thanks for the data. That was just what I was looking for.

From that data it looks like it will have very minimal impact on the current over the voltage range of interest. But if I am using this to save adding a Zener diode but I have to have the part painted... doesn\'t seem worth the trouble. The case only has small air openings, but it has a large port on top covered by plexi so the workings can be monitored. So it will have indirect light inside the case falling on the LED. The case is stainless steel, so lots of reflection.

I wonder just how much the light will affect the LED. Low uA won\'t be a problem. 100\'s of uA will. Sounds like I should use the Zener.

I have no recorded data about the photoelectric effect but,
speaking from memory of a half-hearted test I once did, I can
assure you that it will not be hundreds of uA. I doubt that it
will even be in the \"low uA\" region under those conditions.

 

[John Larkin]

On Wed, 15 Jul 2020 12:17:41 +0530, Pimpom <nobody@nowhere.com> wrote:

On 7/15/2020 10:06 AM, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU. However, I can\'t find a good chart of the I-V curve below 1 mA. The circuit supplies up to 1.15 mA which is measured by dropping it across a 1.5 k resistor yielding up to around 1.7 volts. This seems like it might be getting into a range where the LED might be stealing a significant portion of the current being measured. But none of the references I can find provide enough detail to know for sure. Most seem to be something along the lines of an \"artist\'s concept\" of a curve lying along the X axis until reaching some voltage where it takes off like a hockey stick. Others just seem to be a wag with only a very few points measured. None of them show any detail at the low end with 10 mA as the lowest line on the Y axis.

Anyone measured a green LED at low currents or know how they respond?

If needed, I can lower the resistor which will lower the voltage the LED will see, but I can\'t lower it too much or lose resolution of the measurement.

Maybe I should just give in and limit the voltage with a Zener diode. I was trying to keep a part off the BOM if possible. There\'s already a green LED in use.



I did a manual measurement of various no-name LEDs 10 years ago.
It included only one green 5mm LED. The current level probably
doesn\'t go as low as you want but FWIW this is what I got:

mA V

0.44 -- 2.608
0.5 --- 2.627
1 ----- 2.711
2 ----- 2.801
3 ----- 2.864
4 ----- 2.902
5 ----- 2.939
7 ----- 3.003
10 ---- 3.077
15.5 -- 3.141

Here is my brightness cheat-sheet.

https://www.dropbox.com/s/yql927yu9houa6u/OsramCurrents.JPG?raw=1


I love the Osram orange. It\'s a beautiful pure color.

 

[John Larkin]

On Wed, 15 Jul 2020 12:17:41 +0530, Pimpom <nobody@nowhere.com> wrote:

On 7/15/2020 10:06 AM, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU. However, I can\'t find a good chart of the I-V curve below 1 mA. The circuit supplies up to 1.15 mA which is measured by dropping it across a 1.5 k resistor yielding up to around 1.7 volts. This seems like it might be getting into a range where the LED might be stealing a significant portion of the current being measured. But none of the references I can find provide enough detail to know for sure. Most seem to be something along the lines of an \"artist\'s concept\" of a curve lying along the X axis until reaching some voltage where it takes off like a hockey stick. Others just seem to be a wag with only a very few points measured. None of them show any detail at the low end with 10 mA as the lowest line on the Y axis.

Anyone measured a green LED at low currents or know how they respond?

If needed, I can lower the resistor which will lower the voltage the LED will see, but I can\'t lower it too much or lose resolution of the measurement.

Maybe I should just give in and limit the voltage with a Zener diode. I was trying to keep a part off the BOM if possible. There\'s already a green LED in use.



I did a manual measurement of various no-name LEDs 10 years ago.
It included only one green 5mm LED. The current level probably
doesn\'t go as low as you want but FWIW this is what I got:

mA V

0.44 -- 2.608
0.5 --- 2.627
1 ----- 2.711
2 ----- 2.801
3 ----- 2.864
4 ----- 2.902
5 ----- 2.939
7 ----- 3.003
10 ---- 3.077
15.5 -- 3.141

Here is my brightness cheat-sheet.

https://www.dropbox.com/s/yql927yu9houa6u/OsramCurrents.JPG?raw=1


I love the Osram orange. It\'s a beautiful pure color.

 

[Pimpom]

On 7/15/2020 7:45 PM, jlarkin@highlandsniptechnology.com wrote:

On Wed, 15 Jul 2020 06:11:08 -0700 (PDT), mpm <mpmillard@aol.com
wrote:

On Wednesday, July 15, 2020 at 12:36:26 AM UTC-4, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU.

In the distant past, I have NOT had much success with using diodes to clamp ADC inputs. (Unless you can afford to jettison 4 or 5 bits, or more, of resolution?) The last time I tried it, I found that the diodes (Zener\'s) really affected the voltage much too early in the curve and I couldn\'t calibrate it out with reasonable effort. I ended up just taking them out, for the much improved response.

But maybe that\'s not what you\'re doing here. (?)
And I don\'t think it is, so just mentioning the above.

As for green LED currents, we recently started using one that is amazingly bright at only 330 microamps. I\'ll send you the part# when I get to the office.

I have some green LEDs that are visible in average room light at 1 uA,
and visible to a dark-adapted eye, up close, at 1 nA. Had to get out
of bed at 2AM in Truckee to measure that.

A fun experiment would be to use a PMT and some signal averaging to
see if any photons are emitted at, say, 1 pA.

One of my most common causes of writing ECOs against new designs is
that the LEDs are too bright. Gotta do that again today.

LEDs have come a long way since the early days. I remember when
it was customary to drive a red power indicator LED with 10 mA or
higher. Now I often use 1mA or less with ordinary >1-cent LEDs.

 

[Lasse Langwadt Christensen]

onsdag den 15. juli 2020 kl. 22.46.06 UTC+2 skrev Ricketty C:

On Wednesday, July 15, 2020 at 4:19:31 PM UTC-4, Lasse Langwadt Christensen wrote:
onsdag den 15. juli 2020 kl. 21.55.04 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 2:13:16 PM UTC-4, Lasse Langwadt Christensen wrote:
onsdag den 15. juli 2020 kl. 20.04.55 UTC+2 skrev Ricketty C:
On Wednesday, July 15, 2020 at 12:47:46 PM UTC-4, Pimpom wrote:
On 7/15/2020 9:14 PM, Joe Gwinn wrote:
On 15 Jul 2020 14:32:46 GMT, Rob <nomail@example.com> wrote:

jlarkin@highlandsniptechnology.com <jlarkin@highlandsniptechnology.com> wrote:
One of my most common causes of writing ECOs against new designs is
that the LEDs are too bright. Gotta do that again today.

It is even more true for blue leds than for green. When a device
has a blue indicator LED, it usually is far too bright. Both my PC
and my router have indicator lights that, when not taped over, cause
a large blue spot to appear on the opposite wall.

The best use of this I\'ve seen is Bosch dishwashers, the models that
have no visible controls or indicators when the door is closed:

They use a blue LED to project a spot on the floor - if the spot is
steady, the diswasher is happily progressing through its cycle. If
blinking, go figure out why.

I used a blue LED projection as an indicator in a custom-built
product I made last year. The central unit is housed in a white
plastic box which is completely closed except for an antenna and
a USB port. Going by a last minute inspiration, I projected the
blue LED at the inside of the box from about 2cm away instead of
having it poke through the wall. The result is a diffused circle
of blue light. The customer loved it. The LED current is 1.5mA.

I think I\'ve seen clock that show their LEDs through a white plastic case. Blue LEDs behind white are very attractive I think. I much prefer blue LEDs to red ones.


I\'m sure I\'ve seen some standard that specifies that red should be reserved for errors and warnings

You can find red LED clocks all over the place. I think that standard applies only to indicators intended to indicate status, not time keeping numeric LEDs.


maybe that is just a side effect of red being first led color and thus most commonly available?

Not sure what that means, \"most commonly available\". They make them in many colors, so obviously there\'s no shortage.

sure, now you can get anything you want, I thought it was obvious that
I meant historically LEDs started out a red and maybe that just stuck
as the color used out of old habit

I think they sell what people buy and mostly people buy on very frivolous matters when all else is equal. I bought a used alarm clock once because I couldn\'t find a decent blue one in the stores. lol $10 shipped. It was actually for a girlfriend to go next to her TV, but she moved and I ended up with it.

I would say most people just prefer the red in LED clocks.

blue light is probably a bad choice for an alarm clock, blue light affects melatonin production and allegedly mess with up you sleep

 

[whit3rd]

On Wednesday, July 15, 2020 at 1:27:25 PM UTC-7, John Larkin wrote:

On Wed, 15 Jul 2020 12:45:40 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Wednesday, July 15, 2020 at 12:31:37 PM UTC-7, John Larkin wrote:

Look at the covid case curves. They went linear very early on, at a
few per cent of the ultimate peak.

Don\'t you people ever analyze systems?

That\'s not analysis, when you aggregate all cases into curves.

Are single cases exponential? Would you graph single cases?

Huh?

How can you plot the progress of an epidemic without aggregating
cases?

You don\'t do analysis when you plot the progress, that\'s data collection
and graphic representation.
..
Putting the data onto a single graph means you\'re looking at the sum totals,
not that you\'re looking at the parts. It isn\'t analysis.

> Word salad. Insults. That\'s all you\'ve got.

The word salad is YOUR MISUSE OF THE WORD ANALYSIS.
I\'ve got a dictionary. You don\'t?

 

[John Larkin]

On Wed, 15 Jul 2020 12:45:40 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:

On Wednesday, July 15, 2020 at 12:31:37 PM UTC-7, John Larkin wrote:

Look at the covid case curves. They went linear very early on, at a
few per cent of the ultimate peak.

Don\'t you people ever analyze systems?

That\'s not analysis, when you aggregate all cases into curves.

Are single cases exponential? Would you graph single cases?

How can you plot the progress of an epidemic without aggregating
cases?

Analysis is breaking down the situation into parts, and dealing individually
with the parts.
Drastic measures taken to control the spread of the disease... those are
important parts, and aren\'t visible without analysis. That\'s why John Larkin
doesn\'t see the importance; he\'s not conversant with the analysis principle.

Word salad. Insults. That\'s all you\'ve got.

 

[Joe Gwinn]

On Wed, 15 Jul 2020 10:45:11 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

On Wed, 15 Jul 2020 12:15:13 -0400, Joe Gwinn <joegwinn@comcast.net
wrote:

Micron Dynamics claims that the technology is patented, so I sent an
email asking for patent numbers.
Joe Gwinn

It should be Micron Digital, not Dynamics.

Same company name, but in Hong Kong:
Wearable wireless HMI device
https://patents.google.com/patent/US10318000B2/en
2017-12-11 Application filed by Micron Digital Corp (hk) Limited)
You\'re looking for a company in Canada, not Hong Kong.

I couldn\'t find any other patents under \"Micron Digital\".

Their email is <contact@microndigital.com>. No reply just yet.

This might be the company president:
https://www.linkedin.com/in/rohit-seth-8478a7150/?originalSubdomain=ca

Rohit Seth. Who is in Canada, not HK. And his company is in a suburb
of Toronto. It\'s sounding good so far. Thanks. Time for more
digging.

Joe Gwinn

 

[Joe Gwinn]

On Wed, 15 Jul 2020 10:45:11 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

On Wed, 15 Jul 2020 12:15:13 -0400, Joe Gwinn <joegwinn@comcast.net
wrote:

Micron Dynamics claims that the technology is patented, so I sent an
email asking for patent numbers.
Joe Gwinn

It should be Micron Digital, not Dynamics.

Same company name, but in Hong Kong:
Wearable wireless HMI device
https://patents.google.com/patent/US10318000B2/en
2017-12-11 Application filed by Micron Digital Corp (hk) Limited)
You\'re looking for a company in Canada, not Hong Kong.

I couldn\'t find any other patents under \"Micron Digital\".

Their email is <contact@microndigital.com>. No reply just yet.

This might be the company president:
https://www.linkedin.com/in/rohit-seth-8478a7150/?originalSubdomain=ca

Rohit Seth. Who is in Canada, not HK. And his company is in a suburb
of Toronto. It\'s sounding good so far. Thanks. Time for more
digging.

Joe Gwinn

 

[Pimpom]

On 7/15/2020 7:45 PM, jlarkin@highlandsniptechnology.com wrote:

On Wed, 15 Jul 2020 06:11:08 -0700 (PDT), mpm <mpmillard@aol.com
wrote:

On Wednesday, July 15, 2020 at 12:36:26 AM UTC-4, Ricketty C wrote:
I was thinking of using a green LED to limit a measured voltage on the ADC of an MCU.

In the distant past, I have NOT had much success with using diodes to clamp ADC inputs. (Unless you can afford to jettison 4 or 5 bits, or more, of resolution?) The last time I tried it, I found that the diodes (Zener\'s) really affected the voltage much too early in the curve and I couldn\'t calibrate it out with reasonable effort. I ended up just taking them out, for the much improved response.

But maybe that\'s not what you\'re doing here. (?)
And I don\'t think it is, so just mentioning the above.

As for green LED currents, we recently started using one that is amazingly bright at only 330 microamps. I\'ll send you the part# when I get to the office.

I have some green LEDs that are visible in average room light at 1 uA,
and visible to a dark-adapted eye, up close, at 1 nA. Had to get out
of bed at 2AM in Truckee to measure that.

A fun experiment would be to use a PMT and some signal averaging to
see if any photons are emitted at, say, 1 pA.

One of my most common causes of writing ECOs against new designs is
that the LEDs are too bright. Gotta do that again today.

LEDs have come a long way since the early days. I remember when
it was customary to drive a red power indicator LED with 10 mA or
higher. Now I often use 1mA or less with ordinary >1-cent LEDs.

 

[Simon S Aysdie]

On Wednesday, July 15, 2020 at 1:33:18 PM UTC-7, John Larkin wrote:

On Wed, 15 Jul 2020 12:38:20 -0700 (PDT), Simon S Aysdie
gwhite@ti.com> wrote:

On Tuesday, July 14, 2020 at 6:01:54 AM UTC-7, Phil Hobbs wrote:
So I was chatting with my local Mini Circuits rep, who also handles
Gowanda. He asked if I was interested in conical inductors, which I
certainly am, and how much I wanted to pay for them.

Remembering that JL had said that the Coilcraft patent had expired, I
said \"forty cents in reels\".

Turns out that Gowanda won\'t go below $10 apiece in reels. I pointed
out that I mostly wanted to use it with BFP640s and really wasn\'t going
to use a $10 inductor to decouple a 20-cent transistor--especially since
I can use series-connected 0201/0402/0603 inductors and beads to do
almost as good a job, for $0.12 total.

Those things are just ordinary ferrite or powdered iron, wound with
ordinary copper, and can\'t be that hard to make, so once the patent(s)
expire, it\'s hard to imagine how they can maintain that pricing level.

What gives, do you suppose?

I suppose they are harder to make than we\'d like, although I don\'t know why.

I have used Gowanda and Piconics. Yep--still pricy even though the patents are out.

My latest idea is to emulate a conical with a series of 2-4 \"stepped sizes\" of CCI ferrite core 0201,0402, 0603 inductors. I haven\'t had time to develop a library of \"favorite combinations.\" Some people are hesitant to use these coils above the first self resonance, but it is fine to do so.

We\'ve done series strings of inductors and beads, but they do have
resonances that need additional damping parts. This is time domain,
where we want very clean step responses. For RF, you wouldn\'t need to
be so pickey.

Yeah, you\'re right. This is a nice paper giving the general idea to improve step response, although it is low frequency.

https://www.wb9jps.com/Gary_Johnson/Bias_Tee.html
https://www.wb9jps.com/Gary_Johnson/Bias_Tee_files/Bias_Tee_Design_V2R.pdf

 

[Simon S Aysdie]

On Wednesday, July 15, 2020 at 1:33:18 PM UTC-7, John Larkin wrote:

On Wed, 15 Jul 2020 12:38:20 -0700 (PDT), Simon S Aysdie
gwhite@ti.com> wrote:

On Tuesday, July 14, 2020 at 6:01:54 AM UTC-7, Phil Hobbs wrote:
So I was chatting with my local Mini Circuits rep, who also handles
Gowanda. He asked if I was interested in conical inductors, which I
certainly am, and how much I wanted to pay for them.

Remembering that JL had said that the Coilcraft patent had expired, I
said \"forty cents in reels\".

Turns out that Gowanda won\'t go below $10 apiece in reels. I pointed
out that I mostly wanted to use it with BFP640s and really wasn\'t going
to use a $10 inductor to decouple a 20-cent transistor--especially since
I can use series-connected 0201/0402/0603 inductors and beads to do
almost as good a job, for $0.12 total.

Those things are just ordinary ferrite or powdered iron, wound with
ordinary copper, and can\'t be that hard to make, so once the patent(s)
expire, it\'s hard to imagine how they can maintain that pricing level.

What gives, do you suppose?

I suppose they are harder to make than we\'d like, although I don\'t know why.

I have used Gowanda and Piconics. Yep--still pricy even though the patents are out.

My latest idea is to emulate a conical with a series of 2-4 \"stepped sizes\" of CCI ferrite core 0201,0402, 0603 inductors. I haven\'t had time to develop a library of \"favorite combinations.\" Some people are hesitant to use these coils above the first self resonance, but it is fine to do so.

We\'ve done series strings of inductors and beads, but they do have
resonances that need additional damping parts. This is time domain,
where we want very clean step responses. For RF, you wouldn\'t need to
be so pickey.

Yeah, you\'re right. This is a nice paper giving the general idea to improve step response, although it is low frequency.

https://www.wb9jps.com/Gary_Johnson/Bias_Tee.html
https://www.wb9jps.com/Gary_Johnson/Bias_Tee_files/Bias_Tee_Design_V2R.pdf

 

[Simon S Aysdie]

On Wednesday, July 15, 2020 at 1:33:18 PM UTC-7, John Larkin wrote:

On Wed, 15 Jul 2020 12:38:20 -0700 (PDT), Simon S Aysdie
gwhite@ti.com> wrote:

On Tuesday, July 14, 2020 at 6:01:54 AM UTC-7, Phil Hobbs wrote:
So I was chatting with my local Mini Circuits rep, who also handles
Gowanda. He asked if I was interested in conical inductors, which I
certainly am, and how much I wanted to pay for them.

Remembering that JL had said that the Coilcraft patent had expired, I
said \"forty cents in reels\".

Turns out that Gowanda won\'t go below $10 apiece in reels. I pointed
out that I mostly wanted to use it with BFP640s and really wasn\'t going
to use a $10 inductor to decouple a 20-cent transistor--especially since
I can use series-connected 0201/0402/0603 inductors and beads to do
almost as good a job, for $0.12 total.

Those things are just ordinary ferrite or powdered iron, wound with
ordinary copper, and can\'t be that hard to make, so once the patent(s)
expire, it\'s hard to imagine how they can maintain that pricing level.

What gives, do you suppose?

I suppose they are harder to make than we\'d like, although I don\'t know why.

I have used Gowanda and Piconics. Yep--still pricy even though the patents are out.

My latest idea is to emulate a conical with a series of 2-4 \"stepped sizes\" of CCI ferrite core 0201,0402, 0603 inductors. I haven\'t had time to develop a library of \"favorite combinations.\" Some people are hesitant to use these coils above the first self resonance, but it is fine to do so.

We\'ve done series strings of inductors and beads, but they do have
resonances that need additional damping parts. This is time domain,
where we want very clean step responses. For RF, you wouldn\'t need to
be so pickey.

Yeah, you\'re right. This is a nice paper giving the general idea to improve step response, although it is low frequency.

https://www.wb9jps.com/Gary_Johnson/Bias_Tee.html
https://www.wb9jps.com/Gary_Johnson/Bias_Tee_files/Bias_Tee_Design_V2R.pdf

 

[Phil Hobbs]

On 2020-07-15 15:38, Simon S Aysdie wrote:

On Tuesday, July 14, 2020 at 6:01:54 AM UTC-7, Phil Hobbs wrote:
So I was chatting with my local Mini Circuits rep, who also
handles Gowanda. He asked if I was interested in conical
inductors, which I certainly am, and how much I wanted to pay for
them.

Remembering that JL had said that the Coilcraft patent had expired,
I said \"forty cents in reels\".

Turns out that Gowanda won\'t go below $10 apiece in reels. I
pointed out that I mostly wanted to use it with BFP640s and really
wasn\'t going to use a $10 inductor to decouple a 20-cent
transistor--especially since I can use series-connected
0201/0402/0603 inductors and beads to do almost as good a job, for
$0.12 total.

Those things are just ordinary ferrite or powdered iron, wound
with ordinary copper, and can\'t be that hard to make, so once the
patent(s) expire, it\'s hard to imagine how they can maintain that
pricing level.

What gives, do you suppose?

I suppose they are harder to make than we\'d like, although I don\'t
know why..

I have used Gowanda and Piconics. Yep--still pricy even though the
patents are out.

My latest idea is to emulate a conical with a series of 2-4 \"stepped
sizes\" of CCI ferrite core 0201,0402, 0603 inductors. I haven\'t had
time to develop a library of \"favorite combinations.\" Some people are
hesitant to use these coils above the first self resonance, but it is
fine to do so.

Yup, that\'s my trick too. Starting with the 0402 they\'re actually beads
(Murata BLM15BA/BLM18BB). That helps control the effects of the pads in
between the beads. I haven\'t spent enough time on it to optimize them,
but they\'re pretty good medicine.

For stabilizing BFP640s, I like to use a single BLM15BB050SN1 in the
base. Works like the bomb--I mostly use them for their studly beta,
Early voltage, and low noise--the Infineon model has BF=450, VAF=1000,
and RB=3 ohms, and the 1/f noise corner is pretty low considering it\'s a
40-GHz transistor.

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

 

[Phil Hobbs]

On 2020-07-15 15:38, Simon S Aysdie wrote:

On Tuesday, July 14, 2020 at 6:01:54 AM UTC-7, Phil Hobbs wrote:
So I was chatting with my local Mini Circuits rep, who also
handles Gowanda. He asked if I was interested in conical
inductors, which I certainly am, and how much I wanted to pay for
them.

Remembering that JL had said that the Coilcraft patent had expired,
I said \"forty cents in reels\".

Turns out that Gowanda won\'t go below $10 apiece in reels. I
pointed out that I mostly wanted to use it with BFP640s and really
wasn\'t going to use a $10 inductor to decouple a 20-cent
transistor--especially since I can use series-connected
0201/0402/0603 inductors and beads to do almost as good a job, for
$0.12 total.

Those things are just ordinary ferrite or powdered iron, wound
with ordinary copper, and can\'t be that hard to make, so once the
patent(s) expire, it\'s hard to imagine how they can maintain that
pricing level.

What gives, do you suppose?

I suppose they are harder to make than we\'d like, although I don\'t
know why..

I have used Gowanda and Piconics. Yep--still pricy even though the
patents are out.

My latest idea is to emulate a conical with a series of 2-4 \"stepped
sizes\" of CCI ferrite core 0201,0402, 0603 inductors. I haven\'t had
time to develop a library of \"favorite combinations.\" Some people are
hesitant to use these coils above the first self resonance, but it is
fine to do so.

Yup, that\'s my trick too. Starting with the 0402 they\'re actually beads
(Murata BLM15BA/BLM18BB). That helps control the effects of the pads in
between the beads. I haven\'t spent enough time on it to optimize them,
but they\'re pretty good medicine.

For stabilizing BFP640s, I like to use a single BLM15BB050SN1 in the
base. Works like the bomb--I mostly use them for their studly beta,
Early voltage, and low noise--the Infineon model has BF=450, VAF=1000,
and RB=3 ohms, and the 1/f noise corner is pretty low considering it\'s a
40-GHz transistor.

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