OT: UK to move back to imperial units?

dagmargoodboat@yahoo.com wrote in
news:43923ac6-e740-49ac-a47e-96bbf539a9d0@googlegroups.com:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent,
I'll give you that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I
know all the repertoire of you russian troll crowd. Asking
for agruments against retarded nonsense you post is quite
stadard.

Tell us what you do for a living. Then tell us *when* you do
it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian
troll, he'll keep on babbling as long as he gets paid for his
babble. Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic,
grave-robbing gold digger greedily feeding on the shattered
dreams of a generation. Miss Ono is a multimedia artist." (MAD
Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to
what they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political
posts are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some
of the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10 years
ago was "massive prong"? I have very rarely read this group last
few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur

I am not androgynous. ALL of my posts, regardless of the nym, are
easily ID'd, and no, it does not require "potty mouth", you immature
twerp acting punk. You should refrain from jumping on that hayride,
child. You know it is beneath you.

 

On Tuesday, July 30, 2019 at 2:31:34 PM UTC-4, John Larkin wrote:

On Tue, 30 Jul 2019 09:03:14 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Monday, July 29, 2019 at 10:56:13 PM UTC-4, John Larkin wrote:
On Mon, 29 Jul 2019 18:33:27 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 7/29/19 12:48 PM, John Larkin wrote:
On Mon, 29 Jul 2019 12:13:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

I do a bit of both. Memorizing a few facts helps too, e.g. for thermal
vias, PTH copper is about 40-um thick and small vias (10 mil) are mostly
copper.

We have debated here about whether to pave a copper pour with a lot of
small vias or a fewer number of big ones.

You get more copper per square by using the smallest vias that get the
full metal thickness down in the middle. With a 40-micron copper
thickness, a 10-mil finished hole (250 um) has an unfinished diameter of
250+80 um, i.e.

pi/4*(330 um)**2 = 0.086 mm**2

and the finished hole's area is

pi/4*(250 um)**2 = 0.049 mm**2

so the hole area is 1 - 0.049/0.086 = 42% copper. Plated copper's
alpha is about 380 W/m/K, and FR-4's is about 0.25 W/m/K. So assuming
perfect heat spreaders on both sides, a 1.6 mm board with a rectangular
array of these holes spaced by a distance d will have a thermal
conductance per square metre of

1/theta(d) = (0.049E-6*380/d**2 + 0.25)/0.0016.

For holes on 1.5 mm pitch, this is 5300 W/K/m**2. For a square
centimetre of thermal pad, we get 1E-4 square metres, so

theta = 1/0.53 ~ 2 K/W, not bad, and that's only a 6 x 6 array of holes.

Cheers

Phil Hobbs


You can get 0.2 W/K




My production people don't like vias in pads, so a dpak or SOT89 or
whatever needs to have a solid pad, then a region of solder-masked
topside copper, then copper with a lot of vias. That will work for my
dpak resistor, and I'd be happy to get somewhere near, say, 6 to 8 k/w
overall.

That scheme doesn't work well for power pad parts that have leads all
around. They just have to deal with vias in the pads.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

I'm glad to discover you guys bringing this gem up here (rudely
hijacking an OT thread).

I too came to Phil's calculation that a dense smattering of small vias
laid down the most copper, but got John's lament from assembly houses
that the vias gobble the solder paste. "Don't do that," they said.

Maybe a sensible tack would be using small vias to maximize copper,
then estimating the aggregate void, and then estimating the paste
application adjustment from that, such that the voids are filled and
there's enough solder film left to bond the part.

Pass that info on to manufacturing, and Bob's your Brexit. I mean
uncle.

Grins,
James Arthur

I found a very old bare PCB to play with. Here's a Caddock 50 ohm dpak
being abused.

https://www.dropbox.com/s/2en81s4t2ckkiqt/Caddock_on_TEM.JPG?raw=1

I'm seeing 17 K/W in still air, 13 with a fan. The DPAK is painfully
hot but the copper patch on the bottom of the board (just like the one
on top) is just warm. The vias seem to dominate theta.

My pulse generator can via the dpak to the layer 2 ground pour as well
as to a copper patch on the bottom, so that should be a bit better,
but that klunky via pattern has to be improved.


OT, interesting TDR.

https://www.dropbox.com/s/d1f6cjpf1d97lzs/Ohmite_TDR.JPG?raw=1


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

The spreading resistance is a killer there -- there's
no easy fix besides putting the vias under the device(*),
which is why solving this is rather interesting.

* Well, okay, 1mm Cu buss bar might do a fair job.

Cheers,
James Arthur

 

On Wednesday, July 31, 2019 at 12:22:56 PM UTC-4, Jan Panteltje wrote:

I was reading today that in California now if you want to run for Precedent eeeh president you HAVE to show the taxes
over the last few years.

That won't stand. The Constitution sets the requirements for president,
and California is not allowed to change or add new requirements.

Cheers,
James Arthur

 

On Wednesday, July 31, 2019 at 10:13:22 PM UTC-4, k...@notreal.com wrote:

On Tue, 30 Jul 2019 09:47:52 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 11:29:21 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Tue, 30 Jul 2019 07:56:05 -0700 (PDT)) it happened
dagmargoodboat@yahoo.com wrote in
723c5c5e-3d84-4ea1-acba-2e2b57011ab0@googlegroups.com>:

I can't say. I never watch television.
John Larkin Highland Technology, Inc


That's why it's important we ban books -- they've got no commercials,
plant no tracking cookies, and take too much time away from television.

Exactly, books kill trees so cause glowballworming, are heavy, no online updates,
fire hazard, take too much space, no live experiment movies, sensitive to fungus,
not waterproof, lower data per dollar than google and bing, usually only a one person POV,
and once you have read one all it is good for is fix a wobbling table or something.

I bought an ebook reader some time ago, it has an e-ink display.
is water proof, has WiFi and a bad browser, has some books on it
started reading those ..yuck, no, interfaced it to my navigation system
was all about that display, that is OK:
http://panteltje.com/pub/xgpspc_to_aqua2_IXIMG_0105.JPG
slow refresh... Very good readable in intense sunlight,
you could probably put the work of the great writers here on it,
and save trees.
No color.
I does not do teefee, way to slow.
Solution?
I think not.
Back to the laptop or pad.

I have a Sony e-book reader. E-ink is slick. But as beautiful as
it is, books are better. Much. (The Sony gets next to zero use.)

I use my phone as an e-reader. It's great because I always have it
with me (well, I forgot it at home today) and can read anytime I have
a few minutes to spare. I wouldn't carry any book with me everywhere.

I don't carry a cell phone. I just don't feel the need to be
interrupted 24/7 yet, somehow.

I'm a cell-phone Luddite.

Cheers,
James Arthur

 

On Friday, August 2, 2019 at 10:16:22 PM UTC-4, DecadentLinux...@decadence.org wrote:

dagmargoodboat@yahoo.com wrote in
news:43923ac6-e740-49ac-a47e-96bbf539a9d0@googlegroups.com:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent,
I'll give you that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I
know all the repertoire of you russian troll crowd. Asking
for agruments against retarded nonsense you post is quite
stadard.

Tell us what you do for a living. Then tell us *when* you do
it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian
troll, he'll keep on babbling as long as he gets paid for his
babble. Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic,
grave-robbing gold digger greedily feeding on the shattered
dreams of a generation. Miss Ono is a multimedia artist." (MAD
Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to
what they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political
posts are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some
of the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10 years
ago was "massive prong"? I have very rarely read this group last
few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur


I am not androgynous. ALL of my posts, regardless of the nym, are
easily ID'd, and no, it does not require "potty mouth", you immature
twerp acting punk. You should refrain from jumping on that hayride,
child. You know it is beneath you.

Apologies. I'd meant to not dox you, didn't mean to offend.

James Arthur

 

On Tuesday, July 30, 2019 at 7:48:24 PM UTC-4, whit3rd wrote:

On Tuesday, July 30, 2019 at 9:03:20 AM UTC-7, dagmarg...@yahoo.com wrote:

I too came to Phil's calculation that a dense smattering of small vias
laid down the most copper, but got John's lament from assembly houses
that the vias gobble the solder paste. "Don't do that," they said.

Maybe a sensible tack would be using small vias to maximize copper,
then estimating the aggregate void, and then estimating the paste...

The flaw there, is that the plating doesn't 'throw' as much copper into
small vias, both because the E-field at the throat doesn't penetrate,
and because the circumference is less. Boost the copper plating too much,
and the PTH makes a bump so the pad doesn't rest on the plane.

Mill a hole, and glue a heatpipe to the backside, for real heatsinking. Or
stop trying to mechanically mount by surface-soldering for the high heat parts.

But of course our job is to make a thing as good as it can
be, and still within cost and production goals. Not every product
needs or can afford its own cryo-cooler, so SMD thermal technique
is quite useful.

I made a spreadsheet that calculates d.c. and thermal resistance
of via fields, including empty and solder-filled vias. Lead-free
solder-fill cuts the thermal resistance of a .5mm 3/4oz-plated
via roughly in half; of a .25mm via by about a quarter.

->| |<- .030"
o o o o o
o o o o vias = 0.02", 3/4oz Cu plated, 0.062" FR-4
o o o o o
o o o o

I estimate the above via field at 5.5K/W unfilled, 3.2K/W when
solder-filled.

Best of all is to stuff a bunch of copper plugs in there and
be done with it, but it's not very mass-production friendly.

Maybe big vias filled with copper-filled solder paste would
be a fair compromise in mass-production cases.

Cheers,
James Arthur

 

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:

On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent, I'll give you
that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I know all
the repertoire of you russian troll crowd. Asking for agruments
against retarded nonsense you post is quite stadard.

Tell us what you do for a living. Then tell us *when* you do it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian troll,
he'll keep on babbling as long as he gets paid for his babble.
Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic, grave-robbing
gold digger greedily feeding on the shattered dreams of a
generation. Miss Ono is a multimedia artist." (MAD Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to what
they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political posts
are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some of
the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10 years
ago was "massive prong"? I have very rarely read this group last
few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur

 

[John Larkin]

On Fri, 2 Aug 2019 19:10:39 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent, I'll give you
that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I know all
the repertoire of you russian troll crowd. Asking for agruments
against retarded nonsense you post is quite stadard.

Tell us what you do for a living. Then tell us *when* you do it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian troll,
he'll keep on babbling as long as he gets paid for his babble.
Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic, grave-robbing
gold digger greedily feeding on the shattered dreams of a
generation. Miss Ono is a multimedia artist." (MAD Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to what
they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political posts
are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some of
the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10 years
ago was "massive prong"? I have very rarely read this group last
few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur

The linux guy used to call himself Massive Prong, which I morphed into
Mini Thong, and finally settled on Always Wrong. I think he's the same
guy, likely a tech. His style is distinct, probably not C.D.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[John Larkin]

On Fri, 2 Aug 2019 19:16:41 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 2:31:34 PM UTC-4, John Larkin wrote:
On Tue, 30 Jul 2019 09:03:14 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Monday, July 29, 2019 at 10:56:13 PM UTC-4, John Larkin wrote:
On Mon, 29 Jul 2019 18:33:27 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 7/29/19 12:48 PM, John Larkin wrote:
On Mon, 29 Jul 2019 12:13:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

I do a bit of both. Memorizing a few facts helps too, e.g. for thermal
vias, PTH copper is about 40-um thick and small vias (10 mil) are mostly
copper.

We have debated here about whether to pave a copper pour with a lot of
small vias or a fewer number of big ones.

You get more copper per square by using the smallest vias that get the
full metal thickness down in the middle. With a 40-micron copper
thickness, a 10-mil finished hole (250 um) has an unfinished diameter of
250+80 um, i.e.

pi/4*(330 um)**2 = 0.086 mm**2

and the finished hole's area is

pi/4*(250 um)**2 = 0.049 mm**2

so the hole area is 1 - 0.049/0.086 = 42% copper. Plated copper's
alpha is about 380 W/m/K, and FR-4's is about 0.25 W/m/K. So assuming
perfect heat spreaders on both sides, a 1.6 mm board with a rectangular
array of these holes spaced by a distance d will have a thermal
conductance per square metre of

1/theta(d) = (0.049E-6*380/d**2 + 0.25)/0.0016.

For holes on 1.5 mm pitch, this is 5300 W/K/m**2. For a square
centimetre of thermal pad, we get 1E-4 square metres, so

theta = 1/0.53 ~ 2 K/W, not bad, and that's only a 6 x 6 array of holes.

Cheers

Phil Hobbs


You can get 0.2 W/K




My production people don't like vias in pads, so a dpak or SOT89 or
whatever needs to have a solid pad, then a region of solder-masked
topside copper, then copper with a lot of vias. That will work for my
dpak resistor, and I'd be happy to get somewhere near, say, 6 to 8 k/w
overall.

That scheme doesn't work well for power pad parts that have leads all
around. They just have to deal with vias in the pads.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

I'm glad to discover you guys bringing this gem up here (rudely
hijacking an OT thread).

I too came to Phil's calculation that a dense smattering of small vias
laid down the most copper, but got John's lament from assembly houses
that the vias gobble the solder paste. "Don't do that," they said.

Maybe a sensible tack would be using small vias to maximize copper,
then estimating the aggregate void, and then estimating the paste
application adjustment from that, such that the voids are filled and
there's enough solder film left to bond the part.

Pass that info on to manufacturing, and Bob's your Brexit. I mean
uncle.

Grins,
James Arthur

I found a very old bare PCB to play with. Here's a Caddock 50 ohm dpak
being abused.

https://www.dropbox.com/s/2en81s4t2ckkiqt/Caddock_on_TEM.JPG?raw=1

I'm seeing 17 K/W in still air, 13 with a fan. The DPAK is painfully
hot but the copper patch on the bottom of the board (just like the one
on top) is just warm. The vias seem to dominate theta.

My pulse generator can via the dpak to the layer 2 ground pour as well
as to a copper patch on the bottom, so that should be a bit better,
but that klunky via pattern has to be improved.


OT, interesting TDR.

https://www.dropbox.com/s/d1f6cjpf1d97lzs/Ohmite_TDR.JPG?raw=1


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

The spreading resistance is a killer there -- there's
no easy fix besides putting the vias under the device(*),
which is why solving this is rather interesting.

Maybe not. 1 oz copper is about 70 k/w per square. I can probably
surround the dpak with 12 or maybe 15 squares of copper before I hit
the sea of vias, so the spreading part could be maybe 5 k/w. With a
lot of solder-filled vias, I could possibly get the net dpak below 10
k/w. The trick would be to get the vias very close to the part tab
without annoying manufacturing too much.

Then if I dissipate 8 watts, it will only rise 80K!

We'll try it.



--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Bill Sloman]

On Saturday, August 3, 2019 at 12:10:42 PM UTC+10, dagmarg...@yahoo.com wrote:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

<snip>

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian troll,
he'll keep on babbling as long as he gets paid for his babble.
Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

James Arthur may not be a nitwit, but he's certainly right-wing. Cursitor Doom reliably posts orthodox right-wing nonsense, which happens to be neither entertaining or hetrodox - I call him a gullible twit.

Cursitor Doom's electronics-related posts are remarkably infrequent, and just as worthless as his political propaganda.

Quite how James Arthur knows that he isn't a Russian troll isn't clear - perhaps James Arthur is one himself. James Arthur has admitted to being a paid lackey of the Koch brothers, which is not something one would expect of a Russian troll, but a multi-tasking consultant would be able to serve more than one customer at once.

--
Bill Sloman, Sydney

 

On Fri, 2 Aug 2019 19:28:43 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Wednesday, July 31, 2019 at 10:13:22 PM UTC-4, k...@notreal.com wrote:
On Tue, 30 Jul 2019 09:47:52 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 11:29:21 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Tue, 30 Jul 2019 07:56:05 -0700 (PDT)) it happened
dagmargoodboat@yahoo.com wrote in
723c5c5e-3d84-4ea1-acba-2e2b57011ab0@googlegroups.com>:

I can't say. I never watch television.
John Larkin Highland Technology, Inc


That's why it's important we ban books -- they've got no commercials,
plant no tracking cookies, and take too much time away from television.

Exactly, books kill trees so cause glowballworming, are heavy, no online updates,
fire hazard, take too much space, no live experiment movies, sensitive to fungus,
not waterproof, lower data per dollar than google and bing, usually only a one person POV,
and once you have read one all it is good for is fix a wobbling table or something.

I bought an ebook reader some time ago, it has an e-ink display.
is water proof, has WiFi and a bad browser, has some books on it
started reading those ..yuck, no, interfaced it to my navigation system
was all about that display, that is OK:
http://panteltje.com/pub/xgpspc_to_aqua2_IXIMG_0105.JPG
slow refresh... Very good readable in intense sunlight,
you could probably put the work of the great writers here on it,
and save trees.
No color.
I does not do teefee, way to slow.
Solution?
I think not.
Back to the laptop or pad.

I have a Sony e-book reader. E-ink is slick. But as beautiful as
it is, books are better. Much. (The Sony gets next to zero use.)

I use my phone as an e-reader. It's great because I always have it
with me (well, I forgot it at home today) and can read anytime I have
a few minutes to spare. I wouldn't carry any book with me everywhere.

I don't carry a cell phone. I just don't feel the need to be
interrupted 24/7 yet, somehow.

Yeah, I get interrupted a lot. Maybe two or three phone calls a month
and a few texts a week from my wife. OTOH, it allows me to work when
away from my desk, in addition to being damned handy as an e-reader
for those times when I'm forced to wait for others.

I'm a cell-phone Luddite.

Apparently.

 

On Friday, August 2, 2019 at 11:31:22 PM UTC-4, John Larkin wrote:

On Fri, 2 Aug 2019 19:10:39 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent, I'll give you
that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I know all
the repertoire of you russian troll crowd. Asking for agruments
against retarded nonsense you post is quite stadard.

Tell us what you do for a living. Then tell us *when* you do it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian troll,
he'll keep on babbling as long as he gets paid for his babble.
Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic, grave-robbing
gold digger greedily feeding on the shattered dreams of a
generation. Miss Ono is a multimedia artist." (MAD Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to what
they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political posts
are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some of
the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10 years
ago was "massive prong"? I have very rarely read this group last
few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur

The linux guy used to call himself Massive Prong, which I morphed into
Mini Thong, and finally settled on Always Wrong. I think he's the same
guy, likely a tech. His style is distinct, probably not C.D.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

I don't have any trouble telling them all apart within a
few sentences. It's weird (to me) that others can't. Brains
are weird and wonderful.

Ages ago at Epcot Center, the SYL could identify all sorts
of historical figures from their eyes alone; I couldn't
identify any of them.

"It's easy," she said, "just look at them."

I did. It didn't help.

Cheers,
James

 

[Rick C]

On Friday, August 2, 2019 at 10:22:08 PM UTC-4, dagmarg...@yahoo.com wrote:

On Wednesday, July 31, 2019 at 12:22:56 PM UTC-4, Jan Panteltje wrote:

I was reading today that in California now if you want to run for Precedent eeeh president you HAVE to show the taxes
over the last few years.

That won't stand. The Constitution sets the requirements for president,
and California is not allowed to change or add new requirements.

That's total BS. Each state sets requirements for getting your name on the ballot in that state. It's been this way as long as I remember.

--

Rick C.

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

 

John Larkin <jjlarkin@highlandtechnology.com> wrote in
news:lmv9ketqupktmbi21ea28b4prrkd86a43q@4ax.com:

On Fri, 2 Aug 2019 19:10:39 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 9:04:33 PM UTC-4, dp wrote:
On 7/30/2019 18:35, dagmargoodboat@yahoo.com wrote:
On Sunday, July 28, 2019 at 6:09:34 PM UTC-4, dp wrote:
On 7/28/2019 23:43, Tom Gardner wrote:
On 28/07/19 17:01, Dimiter_Popoff wrote:
On 7/28/2019 17:16, Cursitor Doom wrote:
On Sun, 28 Jul 2019 15:24:19 +0300, Dimiter_Popoff wrote:

If anything, you trolls are both voicy and persistent,
I'll give you that.

So says someone who's obviously got no counter argument.






Yeah yeah, like I said in another post on another topic I
know all the repertoire of you russian troll crowd. Asking
for agruments against retarded nonsense you post is quite
stadard.

Tell us what you do for a living. Then tell us *when* you
do it.

He should also tell us which country he lives in, because
he has stated it isn't part of the UK, viz...

He will tell neither. His behaviour is standard for a russian
troll, he'll keep on babbling as long as he gets paid for his
babble. Pathetic way to earn a living.

Cursitor Doom has been posting entertaining heterodoxy and
electronics-related postings here for decades. He is not a
Russian troll. He's a hobbyist.

Cheers,
James Arthur

~~~~~~~~~~
"Correction: An item in last month's 'Entertainment' section
incorrectly identified Yoko Ono as a cannibalistic,
grave-robbing gold digger greedily feeding on the shattered
dreams of a generation. Miss Ono is a multimedia artist."
(MAD Magazine, c. 1980)


Hmm. He certainly sings the songs Russian trolls sing, 1:1 to
what they push on Bulgarian news comment sections etc.
I genuinely thought he was one of them trolls, his political
posts are certainly what a Russian troll would post.

Probably he just parrots what he has been subjected to via some
of the media the Russians have in their pocket.

Is he the "always wrong" guy and the guy who may be some 10
years ago was "massive prong"? I have very rarely read this
group last few years so I could not tell.

Nah, Always Wrong / Missing Prong's another guy, presently using
another nym. Easily identified by the potty talk.

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'


Cheers,
James Arthur

The linux guy used to call himself Massive Prong, which I morphed
into Mini Thong, and finally settled on Always Wrong. I think he's
the same guy, likely a tech. His style is distinct, probably not
C.D.

Get Terrell to post his 'lits'. Or was that Thompson?

I'd bet KRW has it.

 

On Friday, August 2, 2019 at 11:42:31 PM UTC-4, John Larkin wrote:

On Fri, 2 Aug 2019 19:16:41 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Tuesday, July 30, 2019 at 2:31:34 PM UTC-4, John Larkin wrote:
On Tue, 30 Jul 2019 09:03:14 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Monday, July 29, 2019 at 10:56:13 PM UTC-4, John Larkin wrote:
On Mon, 29 Jul 2019 18:33:27 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 7/29/19 12:48 PM, John Larkin wrote:
On Mon, 29 Jul 2019 12:13:25 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

I do a bit of both. Memorizing a few facts helps too, e.g. for thermal
vias, PTH copper is about 40-um thick and small vias (10 mil) are mostly
copper.

We have debated here about whether to pave a copper pour with a lot of
small vias or a fewer number of big ones.

You get more copper per square by using the smallest vias that get the
full metal thickness down in the middle. With a 40-micron copper
thickness, a 10-mil finished hole (250 um) has an unfinished diameter of
250+80 um, i.e.

pi/4*(330 um)**2 = 0.086 mm**2

and the finished hole's area is

pi/4*(250 um)**2 = 0.049 mm**2

so the hole area is 1 - 0.049/0.086 = 42% copper. Plated copper's
alpha is about 380 W/m/K, and FR-4's is about 0.25 W/m/K. So assuming
perfect heat spreaders on both sides, a 1.6 mm board with a rectangular
array of these holes spaced by a distance d will have a thermal
conductance per square metre of

1/theta(d) = (0.049E-6*380/d**2 + 0.25)/0.0016.

For holes on 1.5 mm pitch, this is 5300 W/K/m**2. For a square
centimetre of thermal pad, we get 1E-4 square metres, so

theta = 1/0.53 ~ 2 K/W, not bad, and that's only a 6 x 6 array of holes.

Cheers

Phil Hobbs


You can get 0.2 W/K




My production people don't like vias in pads, so a dpak or SOT89 or
whatever needs to have a solid pad, then a region of solder-masked
topside copper, then copper with a lot of vias. That will work for my
dpak resistor, and I'd be happy to get somewhere near, say, 6 to 8 k/w
overall.

That scheme doesn't work well for power pad parts that have leads all
around. They just have to deal with vias in the pads.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

I'm glad to discover you guys bringing this gem up here (rudely
hijacking an OT thread).

I too came to Phil's calculation that a dense smattering of small vias
laid down the most copper, but got John's lament from assembly houses
that the vias gobble the solder paste. "Don't do that," they said.

Maybe a sensible tack would be using small vias to maximize copper,
then estimating the aggregate void, and then estimating the paste
application adjustment from that, such that the voids are filled and
there's enough solder film left to bond the part.

Pass that info on to manufacturing, and Bob's your Brexit. I mean
uncle.

Grins,
James Arthur

I found a very old bare PCB to play with. Here's a Caddock 50 ohm dpak
being abused.

https://www.dropbox.com/s/2en81s4t2ckkiqt/Caddock_on_TEM.JPG?raw=1

I'm seeing 17 K/W in still air, 13 with a fan. The DPAK is painfully
hot but the copper patch on the bottom of the board (just like the one
on top) is just warm. The vias seem to dominate theta.

My pulse generator can via the dpak to the layer 2 ground pour as well
as to a copper patch on the bottom, so that should be a bit better,
but that klunky via pattern has to be improved.


OT, interesting TDR.

https://www.dropbox.com/s/d1f6cjpf1d97lzs/Ohmite_TDR.JPG?raw=1


jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

The spreading resistance is a killer there -- there's
no easy fix besides putting the vias under the device(*),
which is why solving this is rather interesting.

Maybe not. 1 oz copper is about 70 k/w per square. I can probably
surround the dpak with 12 or maybe 15 squares of copper before I hit
the sea of vias, so the spreading part could be maybe 5 k/w. With a
lot of solder-filled vias, I could possibly get the net dpak below 10
k/w. The trick would be to get the vias very close to the part tab
without annoying manufacturing too much.

Then if I dissipate 8 watts, it will only rise 80K!

We'll try it.

Above I posted this estimate from basic principles:

->| |<- .030"
o o o o o
o o o o vias = 0.02", 25um Cu plated, 0.062" FR-4
o o o o o
o o o o

I estimated the above via field at 5.5K/W unfilled, 3.2K/W when
solder-filled.

Updating my spreadsheet, it's 0.5K/W when copper-filled.

~~~~~~~~~~~~~

This guy makes and swages in his own copper rivets from soft
copper wire:
https://paulwanamaker.wordpress.com/300-2/

It's pretty simple, actually, and might be handy for
a super-critical bleeding edge product.
.-- swaged surface is recessed, but contacts top trace.
/
/ copper trace
====.___/___.==== /
====|\ V /|====
| | | |
| | | | FR-4
| | | |
| | | |
| | | |
====' '---' '====

Cheers,
James Arthur

 

On Friday, August 2, 2019 at 11:59:41 PM UTC-4, Rick C wrote:

On Friday, August 2, 2019 at 10:22:08 PM UTC-4, dagmarg...@yahoo.com wrote:
On Wednesday, July 31, 2019 at 12:22:56 PM UTC-4, Jan Panteltje wrote:

I was reading today that in California now if you want to run for Precedent eeeh president you HAVE to show the taxes
over the last few years.

That won't stand. The Constitution sets the requirements for president,
and California is not allowed to change or add new requirements.

That's total BS. Each state sets requirements for getting your name on the ballot in that state. It's been this way as long as I remember.

Republicans hold a large majority of state legislative bodies. Would
you be okay with them passing laws preventing qualified Democrat
candidates from running in their states? Under your theory, what stops
them?

It's unconstitutional six ways from Sunday. For one, ISTM it's a bill
of attainder -- a transparent attempt to pass a law meant punish a
particular individual. For another, it's adding requirements on top
of the Constitution's, which clearly states the requirements to be
president.

States don't get to customize the requirements to suit themselves --
that's lawless. Third-world. And very dangerous.

Cheers,
James Arthur

 

[Jan Panteltje]

On a sunny day (Fri, 2 Aug 2019 19:22:04 -0700 (PDT)) it happened
dagmargoodboat@yahoo.com wrote in
<44abf246-d235-4f46-8197-c3b382ad031d@googlegroups.com>:

On Wednesday, July 31, 2019 at 12:22:56 PM UTC-4, Jan Panteltje wrote:

I was reading today that in California now if you want to run for Precedent eeeh president you HAVE to show the taxes
over the last few years.

That won't stand. The Constitution sets the requirements for president,
and California is not allowed to change or add new requirements.

I dunno about all those 'merrican lawsuits,
but it was signed into law by the demoncratetic governor.
The previous governor did not want to sigh it.
it is all over the news:
https://www.smdp.com/california-governor-signs-bill-on-presidential-tax-returns/178060

Are you saying somebody running for Precedent will fight it in court?
California will then likely declare independence
Shortly after followed by Texas, and a few more states.

 

[Rick C]

On Saturday, August 3, 2019 at 1:04:18 AM UTC-4, dagmarg...@yahoo.com wrote:

On Friday, August 2, 2019 at 11:59:41 PM UTC-4, Rick C wrote:
On Friday, August 2, 2019 at 10:22:08 PM UTC-4, dagmarg...@yahoo.com wrote:
On Wednesday, July 31, 2019 at 12:22:56 PM UTC-4, Jan Panteltje wrote:

I was reading today that in California now if you want to run for Precedent eeeh president you HAVE to show the taxes
over the last few years.

That won't stand. The Constitution sets the requirements for president,
and California is not allowed to change or add new requirements.

That's total BS. Each state sets requirements for getting your name on the ballot in that state. It's been this way as long as I remember.

Republicans hold a large majority of state legislative bodies. Would
you be okay with them passing laws preventing qualified Democrat
candidates from running in their states? Under your theory, what stops
them?

It's unconstitutional six ways from Sunday. For one, ISTM it's a bill
of attainder -- a transparent attempt to pass a law meant punish a
particular individual. For another, it's adding requirements on top
of the Constitution's, which clearly states the requirements to be
president.

States don't get to customize the requirements to suit themselves --
that's lawless. Third-world. And very dangerous.

What theory? That's what they do! Try reading something about it.

--

Rick C.

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

 

[Cursitor Doom]

On Fri, 02 Aug 2019 21:28:53 -0700, dagmargoodboat wrote:

Ages ago at Epcot Center, the SYL could identify all sorts of historical
figures from their eyes alone; I couldn't identify any of them.

"It's easy," she said, "just look at them."

I did. It didn't help.

I had an Iranian friend who could identify precisely were any given
person came from to within a few hundred square miles out of the entire
Eurasian land mass just by studying them for a few seconds. Didn't even
need to hear 'em speak, either. Just an amazing natural ability.

The UK Border Force could use people like that in places like Dover.
They'd never get away with the old, "so sorry, lost my passport on the
way" line beloved of so many piss-taking illegal entrants.



--
This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

 

[Cursitor Doom]

On Fri, 02 Aug 2019 19:10:39 -0700, dagmargoodboat wrote:

CD's just a humble U.K.er, whom Hillary would call 'deplorable,'
possibly 'irredeemable.'

I've called *her* a lot worse! :-D



--
This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.