OT: UK to move back to imperial units?

Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> wrote in
news:qi37kq$mue$1@dont-email.me:

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-presidentia
l-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.

No state will ever "succeed" from the US. Not permitted. It is a
union of states, and no, we would not ever allow one to declare
itself as its own country. Too much shit hits the fan in such a
case, so it will NEVER (be allowed to) happen.

 

[Bill Sloman]

On Saturday, August 3, 2019 at 7:30:44 PM UTC+10, Cursitor Doom wrote:

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.

Cursitor Doom is easily amazed. Often by strikingly implausible claims.

--
Bill Sloman, Sydney

 

[Tom Gardner]

On 03/08/19 12:47, Bill Sloman wrote:

On Saturday, August 3, 2019 at 7:30:44 PM UTC+10, Cursitor Doom wrote:
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.

Cursitor Doom is easily amazed. Often by strikingly implausible claims.

Indeed.

The meaning of "where they come from" is extremely ambiguous.
The black comedian Lenny Henry famously wanted to take up
the British National Party (i.e. racist fascist) offer of ÂŁ100
to any (black) person to "go home". After all, he was born
in Dudley Birmingham, and had lived there ever since

However there is the phenomenon used by police: some people
are "super recognisers" with the ability to accurately spot
"faces of interest" in a crowd.

Conceivably CD's anecdote represents a variant of that.

Or perhaps his Iranian friend had convinced /himself/ that
he could do that trick

 

[John Larkin]

On Fri, 2 Aug 2019 22:04:14 -0700 (PDT), dagmargoodboat@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.

Cheers,
James Arthur

There is already Supreme Court precedence that states can't add
qualification to national positions.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Bill Sloman]

On Saturday, August 3, 2019 at 10:29:58 PM UTC+10, Tom Gardner wrote:

On 03/08/19 12:47, Bill Sloman wrote:
On Saturday, August 3, 2019 at 7:30:44 PM UTC+10, Cursitor Doom wrote:
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.

Cursitor Doom is easily amazed. Often by strikingly implausible claims.

Indeed.

The meaning of "where they come from" is extremely ambiguous.
The black comedian Lenny Henry famously wanted to take up
the British National Party (i.e. racist fascist) offer of ÂŁ100
to any (black) person to "go home". After all, he was born
in Dudley Birmingham, and had lived there ever since

However there is the phenomenon used by police: some people
are "super recognisers" with the ability to accurately spot
"faces of interest" in a crowd.

Conceivably CD's anecdote represents a variant of that.

Unlikely. Super recognisers recognise specific human faces.

Cursitor Doom's Iranian friend had to sort out an arbitrary collection of previously unfamiliar faces according to the place where they came from.

There are heritable features that show up in face shape, but they show up all over the place. Hair and clothing styles do vary from place to place but they also vary with social class and religion. It would be neat trick if anybody could pull it off, but granting that Cursitor Doom is a gullible twit, it's a lot more likely that somebody was pulling his leg.

Or perhaps his Iranian friend had convinced /himself/ that
he could do that trick

Also possible. But less likely.

--
Bill Sloman, Sydney

 

[John Larkin]

On Sat, 03 Aug 2019 05:55:35 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

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.

I've met Gavin. He's a total airhead.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Rick C]

On Saturday, August 3, 2019 at 11:04:42 AM UTC-4, John Larkin wrote:

On Fri, 2 Aug 2019 22:04:14 -0700 (PDT), dagmargoodboat@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.

Cheers,
James Arthur

There is already Supreme Court precedence that states can't add
qualification to national positions.

That's not really the issue. The issue is what requirements are in place for a Presidential candidate to be on the ballot. I've not heard of any of these requirements being challenged successfully.

"Qualification" for office is an entirely separate matter.

--

Rick C.

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

 

[John Larkin]

On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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

Might that block solder?

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

My other option is the thermistor shutdown circuit, which is simple.
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

I wonder how Ohmite rates their ceramic DPAK resistor for 45 watts. In
flowing ice water? Soldered to a pure copper brick?



--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

On Saturday, August 3, 2019 at 11:04:42 AM UTC-4, John Larkin wrote:

On Fri, 2 Aug 2019 22:04:14 -0700 (PDT), dagmargoodboat@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.

Cheers,
James Arthur

There is already Supreme Court precedence that states can't add
qualification to national positions.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

It's just so blatantly Third World and unconstitutional one wonders
how we're even in this position -- the schools have clearly failed
to teach our fellow citizens how this whole "freedom" form of
government thing works.

It might be kind of fun though. Various states could add a "trial
by ordeal" requirement, like ice-water immersion, or a minimum
number of pushups.

Or maybe a business-experience requirement, which would weed out
all the professional parasites^H^H^H^H^Hpoliticians.

Cheers,
James Arthur

 

On Saturday, August 3, 2019 at 1:55:42 AM UTC-4, Jan Panteltje wrote:

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.

The previous governor, Jerry Brown, wouldn't sign it because he
(correctly) thought it unconstitutional. But Gavin Newsom went
ahead, so yes, it will certainly be litigated and overturned.

California's gone nuts, and New York, too.

Cheers,
James Arthur

 

On Saturday, August 3, 2019 at 1:56:55 AM UTC-4, Rick C wrote:

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.

IOW you'd be fine with Republican states barring Democrats from running?
And with states setting literacy tests, or only permitting people who can
show they've built at least one hotel? You've no problem with stripping
someone of their Fourth Amendment rights, nor ripping away the Fifth, at
your convenience.

Ah yes, the tyrant's mindset -- it's all so simple, isn't? Just ignore
the law and the Constitution, and do whatever you want to whomever you
please.

But the fact is you're mistaken, and California's law won't stand.

Cheers,
James Arthur

 

[John Larkin]

On Sun, 4 Aug 2019 06:12:47 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Saturday, August 3, 2019 at 1:55:42 AM UTC-4, Jan Panteltje wrote:
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.

The previous governor, Jerry Brown, wouldn't sign it because he
(correctly) thought it unconstitutional. But Gavin Newsom went
ahead, so yes, it will certainly be litigated and overturned.

California's gone nuts, and New York, too.

Cheers,
James Arthur

But California is prettier and has better weather.

And better bread.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Rick C]

On Sunday, August 4, 2019 at 9:04:53 AM UTC-4, dagmarg...@yahoo.com wrote:

On Saturday, August 3, 2019 at 1:56:55 AM UTC-4, Rick C wrote:
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.

IOW you'd be fine with Republican states barring Democrats from running?
And with states setting literacy tests, or only permitting people who can
show they've built at least one hotel? You've no problem with stripping
someone of their Fourth Amendment rights, nor ripping away the Fifth, at
your convenience.

Ah yes, the tyrant's mindset -- it's all so simple, isn't? Just ignore
the law and the Constitution, and do whatever you want to whomever you
please.

But the fact is you're mistaken, and California's law won't stand.

Are you saying states don't each have their own regulations to be on the presidential ballot?

https://lmgtfy.com/?q=presidential+ballot+requirements+by+state

--

Rick C.

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

 

On Saturday, August 3, 2019 at 11:22:29 AM UTC-4, John Larkin wrote:

On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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
| | | |
| | | |
| | | |
====' '---' '====


Might that block solder?

From the via? Oh definitely. But is that a problem? I don't see
why.

He makes his rivets tight-fitting. That maximizes copper cross
section, which seems fine to me.

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

I think I suggested something like that last time this issue
came up -- inserting a number of copper-leaded dummy parts. That
would really confuse people .

My other option is the thermistor shutdown circuit, which is simple.
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

After going though all of this again, I think my preferred move next
time will be a single large via under the thermal tab, filled with a
matching copper plug. A 0.150" copper plug would be simple and could
move a lot of heat (theta = 0.7K/W). Or possibly 4 x 0.100" vias, etc.

#10 wire is 0.102" and #16 is 0.0508", which might be convenient. Or
possibly punch or cut rounds from flat sheet...it's certainly doable.

I wonder how Ohmite rates their ceramic DPAK resistor for 45 watts. In
flowing ice water? Soldered to a pure copper brick?

Or LN2?

Our pal Dan put a small incandescent bulb inside an insulated can once.
Melted the can, IIRC.

Cheers,
James Arthur

 

[John Larkin]

On Sun, 4 Aug 2019 06:51:35 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Saturday, August 3, 2019 at 11:22:29 AM UTC-4, John Larkin wrote:
On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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
| | | |
| | | |
| | | |
====' '---' '====


Might that block solder?

From the via? Oh definitely. But is that a problem? I don't see
why.

He makes his rivets tight-fitting. That maximizes copper cross
section, which seems fine to me.

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

I think I suggested something like that last time this issue
came up -- inserting a number of copper-leaded dummy parts. That
would really confuse people .

My other option is the thermistor shutdown circuit, which is simple.
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

After going though all of this again, I think my preferred move next
time will be a single large via under the thermal tab, filled with a
matching copper plug. A 0.150" copper plug would be simple and could
move a lot of heat (theta = 0.7K/W). Or possibly 4 x 0.100" vias, etc.

#10 wire is 0.102" and #16 is 0.0508", which might be convenient. Or
possibly punch or cut rounds from flat sheet...it's certainly doable.

Amazon and Ebay sell a wide range of punched copper disks, intended
for jewelry use. Probably not pure copper, but pretty good. One of
those could drop into a round hole on a PCB. But then, where would the
heat go?

I wonder how Ohmite rates their ceramic DPAK resistor for 45 watts. In
flowing ice water? Soldered to a pure copper brick?

Or LN2?

Our pal Dan put a small incandescent bulb inside an insulated can once.
Melted the can, IIRC.

Heard from DG lately? Still in Mississippi?




--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

On Sunday, August 4, 2019 at 10:14:58 AM UTC-4, Rick C wrote:

On Sunday, August 4, 2019 at 9:04:53 AM UTC-4, dagmarg...@yahoo.com wrote:
On Saturday, August 3, 2019 at 1:56:55 AM UTC-4, Rick C wrote:
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.

IOW you'd be fine with Republican states barring Democrats from running?
And with states setting literacy tests, or only permitting people who can
show they've built at least one hotel? You've no problem with stripping
someone of their Fourth Amendment rights, nor ripping away the Fifth, at
your convenience.

Ah yes, the tyrant's mindset -- it's all so simple, isn't? Just ignore
the law and the Constitution, and do whatever you want to whomever you
please.

But the fact is you're mistaken, and California's law won't stand.

Are you saying states don't each have their own regulations to be on the presidential ballot?

https://lmgtfy.com/?q=presidential+ballot+requirements+by+state

--

Rick C.

Aren't you equating a) the practical, voter-approval based electoral
necessity of winnowing candidates on the ballot to those with
plausible prospects of winning, with b) the practice of state
legislatures arbitrarily disqualifying particular fully-qualified
candidates solely on the basis of skin-color (orange)?

Seriously Rick, you're not thinking this through. I already gave
several examples of how disastrous your theory would be. You responded
to none of them.

Another reason it's unconstitutional -- the Constitution guarantees
to all citizens the right to a republican form of government, a right
which is denied when the citizens cannot vote for the representatives
of their choosing.

California's law is unconstitutional. It's not even close.

Cheers,
James Arthur

 

On Sunday, August 4, 2019 at 10:37:22 AM UTC-4, John Larkin wrote:

On Sun, 4 Aug 2019 06:51:35 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Saturday, August 3, 2019 at 11:22:29 AM UTC-4, John Larkin wrote:
On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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
| | | |
| | | |
| | | |
====' '---' '====


Might that block solder?

From the via? Oh definitely. But is that a problem? I don't see
why.

He makes his rivets tight-fitting. That maximizes copper cross
section, which seems fine to me.

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

I think I suggested something like that last time this issue
came up -- inserting a number of copper-leaded dummy parts. That
would really confuse people .

My other option is the thermistor shutdown circuit, which is simple.
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

After going though all of this again, I think my preferred move next
time will be a single large via under the thermal tab, filled with a
matching copper plug. A 0.150" copper plug would be simple and could
move a lot of heat (theta = 0.7K/W). Or possibly 4 x 0.100" vias, etc.

#10 wire is 0.102" and #16 is 0.0508", which might be convenient. Or
possibly punch or cut rounds from flat sheet...it's certainly doable.

Amazon and Ebay sell a wide range of punched copper disks, intended
for jewelry use. Probably not pure copper, but pretty good. One of
those could drop into a round hole on a PCB. But then, where would the
heat go?

To the other side. I'm assuming a hairy use needing this level of heat
disposal has a heat sink on the other side. In my case, last time, we
spec'd a milled, finned, aluminum block. Worked great.

I wonder how Ohmite rates their ceramic DPAK resistor for 45 watts. In
flowing ice water? Soldered to a pure copper brick?

Or LN2?

Our pal Dan put a small incandescent bulb inside an insulated can once.
Melted the can, IIRC.

Heard from DG lately? Still in Mississippi?

Yep, spoke to 'im yesterday. As charming and fun as ever.

Cheers,
James

 

[Rick C]

On Sunday, August 4, 2019 at 10:47:37 AM UTC-4, dagmarg...@yahoo.com wrote:

On Sunday, August 4, 2019 at 10:14:58 AM UTC-4, Rick C wrote:
On Sunday, August 4, 2019 at 9:04:53 AM UTC-4, dagmarg...@yahoo.com wrote:
On Saturday, August 3, 2019 at 1:56:55 AM UTC-4, Rick C wrote:
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.

IOW you'd be fine with Republican states barring Democrats from running?
And with states setting literacy tests, or only permitting people who can
show they've built at least one hotel? You've no problem with stripping
someone of their Fourth Amendment rights, nor ripping away the Fifth, at
your convenience.

Ah yes, the tyrant's mindset -- it's all so simple, isn't? Just ignore
the law and the Constitution, and do whatever you want to whomever you
please.

But the fact is you're mistaken, and California's law won't stand.

Are you saying states don't each have their own regulations to be on the presidential ballot?

https://lmgtfy.com/?q=presidential+ballot+requirements+by+state

--

Rick C.


Aren't you equating a) the practical, voter-approval based electoral
necessity of winnowing candidates on the ballot to those with
plausible prospects of winning, with b) the practice of state
legislatures arbitrarily disqualifying particular fully-qualified
candidates solely on the basis of skin-color (orange)?

Seriously Rick, you're not thinking this through. I already gave
several examples of how disastrous your theory would be. You responded
to none of them.

Another reason it's unconstitutional -- the Constitution guarantees
to all citizens the right to a republican form of government, a right
which is denied when the citizens cannot vote for the representatives
of their choosing.

California's law is unconstitutional. It's not even close.

It's not my theory. It's common practice. I don't know why you keep asking about the consequences of *my* idea.

Talk to the states that set requirements for Presidential candidates, not me, about "consequences".

Here are some Constitutional requirements set by states...

CA - The Court found the requirement that the candidate be a member of the independent party for over a year before being allowed to participate in that party's upcoming primary constitutional.

Hawaii banned write-in voting - Here, voters had ample opportunity to participate in elections.

The Hawaii ban is interesting in that I don't follow the reasoning between write-in candidates and voter "ample opportunity"...

--

Rick C.

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

 

[John Larkin]

On Sun, 4 Aug 2019 07:56:42 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Sunday, August 4, 2019 at 10:37:22 AM UTC-4, John Larkin wrote:
On Sun, 4 Aug 2019 06:51:35 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Saturday, August 3, 2019 at 11:22:29 AM UTC-4, John Larkin wrote:
On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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
| | | |
| | | |
| | | |
====' '---' '====


Might that block solder?

From the via? Oh definitely. But is that a problem? I don't see
why.

He makes his rivets tight-fitting. That maximizes copper cross
section, which seems fine to me.

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

I think I suggested something like that last time this issue
came up -- inserting a number of copper-leaded dummy parts. That
would really confuse people .

My other option is the thermistor shutdown circuit, which is simple.
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

After going though all of this again, I think my preferred move next
time will be a single large via under the thermal tab, filled with a
matching copper plug. A 0.150" copper plug would be simple and could
move a lot of heat (theta = 0.7K/W). Or possibly 4 x 0.100" vias, etc.

#10 wire is 0.102" and #16 is 0.0508", which might be convenient. Or
possibly punch or cut rounds from flat sheet...it's certainly doable.

Amazon and Ebay sell a wide range of punched copper disks, intended
for jewelry use. Probably not pure copper, but pretty good. One of
those could drop into a round hole on a PCB. But then, where would the
heat go?

To the other side. I'm assuming a hairy use needing this level of heat
disposal has a heat sink on the other side. In my case, last time, we
spec'd a milled, finned, aluminum block. Worked great.

My board will be in a box, so a heat sink on the bottom would be short
and sitting in dead air. My best option might be to conduct the heat
from the bottom of the board to the bottom of the aluminum box,
through a gap-pad or a sandwich of aluminum and gap-pads (or copper
disks!) The wouldn't be awful, just sandwich the metal with
double-sticky gap-pad stuff and scrunch the PCB on top.

There are AlN resistors that size that are rated for hundreds of
watts.



--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Lasse Langwadt Christense]

søndag den 4. august 2019 kl. 19.00.17 UTC+2 skrev John Larkin:

On Sun, 4 Aug 2019 07:56:42 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Sunday, August 4, 2019 at 10:37:22 AM UTC-4, John Larkin wrote:
On Sun, 4 Aug 2019 06:51:35 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

On Saturday, August 3, 2019 at 11:22:29 AM UTC-4, John Larkin wrote:
On Fri, 2 Aug 2019 21:41:29 -0700 (PDT), dagmargoodboat@yahoo.com
wrote:

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
| | | |
| | | |
| | | |
====' '---' '===

Might that block solder?

From the via? Oh definitely. But is that a problem? I don't see
why.

He makes his rivets tight-fitting. That maximizes copper cross
section, which seems fine to me.

I could build a corral around the dpak by soldering in three ribbon
cable headers, the ones with two rows of square pins on 50 mil
centers. We already use them as jtags. They would fill the holes with
copper+solder and add a tiny bit of additional heat sinking up into
the air themselves.

It would look pleasingly bizarre.

I think I suggested something like that last time this issue
came up -- inserting a number of copper-leaded dummy parts. That
would really confuse people .

My other option is the thermistor shutdown circuit, which is simple..
I'm trying to protect a pulse generator 50 ohm output resistor in the
case that the customer programs a big voltage and then shorts the
load.

After going though all of this again, I think my preferred move next
time will be a single large via under the thermal tab, filled with a
matching copper plug. A 0.150" copper plug would be simple and could
move a lot of heat (theta = 0.7K/W). Or possibly 4 x 0.100" vias, etc.

#10 wire is 0.102" and #16 is 0.0508", which might be convenient. Or
possibly punch or cut rounds from flat sheet...it's certainly doable.

Amazon and Ebay sell a wide range of punched copper disks, intended
for jewelry use. Probably not pure copper, but pretty good. One of
those could drop into a round hole on a PCB. But then, where would the
heat go?

To the other side. I'm assuming a hairy use needing this level of heat
disposal has a heat sink on the other side. In my case, last time, we
spec'd a milled, finned, aluminum block. Worked great.

My board will be in a box, so a heat sink on the bottom would be short
and sitting in dead air. My best option might be to conduct the heat
from the bottom of the board to the bottom of the aluminum box,
through a gap-pad or a sandwich of aluminum and gap-pads (or copper
disks!) The wouldn't be awful, just sandwich the metal with
double-sticky gap-pad stuff and scrunch the PCB on top.

There are AlN resistors that size that are rated for hundreds of
watts.

stick on of these in the pcb before soldering,

https://www.tindie.com/products/TEMProducts/power-smt-pcb-insert/