Driver to drive?

[JosephKK]

On Wed, 05 Aug 2009 21:18:51 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Wed, 05 Aug 2009 20:57:04 -0700,
"JosephKK"<quiettechblue@yahoo.com> wrote:

On Sun, 02 Aug 2009 17:25:17 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sun, 02 Aug 2009 16:45:07 -0700, Robert Baer
robertbaer@localnet.com> wrote:

John Larkin wrote:

<snip>

Ahh.. that is what someone else implied and did *not* specify.
But since i am not into thermal conductivity and/or insulation, the
"meter" does not make sense to me in this context.
Would have to dig into this usage and the units.

Thermal conductivity, in SI units, is specified in watts per
meter-Kelvin.

Aluminum is about 240 w/m-K.

So if you had a 1-meter cube of the stuff, and forced a 1 degree C
difference across opposite faces, 240 watts of heat would flow.

The thermal resistance would be the reciprocal, about 0.004 degrees C
per watt.

Starting from there, it's easy to scale for area and thickness.

Fun fact: the thermal resistance of copper is about 150,000 degs C per
watt per ohm.

The standard unit of thermal conductivity (inverse of thermal
resistance) is W/(m*K), no "ohms" involved. So much for your "fun
fact"

John

Clean up your units please.

Where?

John

QED

--
Transmitted with recycled bits.
Damnly my frank, I don't give a dear
----------

 

[JosephKK]

On Fri, 07 Aug 2009 05:12:47 -0700, John Larkin
<jjSNIPlarkin@highTHISlandtechnology.com> wrote:

On Thu, 06 Aug 2009 22:29:22 -0700, Archimedes' Lever
OneBigLever@InfiniteSeries.Org> wrote:



Use big nylon nuts and bolts. Or glass filled epoxy.

Which don't conduct electricity very well.

John


You do not have to rely on the fasteners to provide the conduction path
between two mating surfaces. In fact, you shouldn't.

I thought you were talking about thermal conduction anyway.

I was talking about the thermal conductivity of electrical conductors.
The same electrons that transport current also transport heat - pretty
much - so most metals are the same as regards how much current you can
carry for a given heat loss. This matters for stuff like getting power
into a crystal oven or a cryogenic gadget, where we really don't want
the heat loss through the leads.

People use stainless and manganin wire to run to really cold (liquid
helium) gadgets so as to not leak too much heat. Google "Garwin
thermal integral" for some messy math.

John

And google John Larkin for occasional very sloppy math/physics/units.

 

[JosephKK]

On Fri, 07 Aug 2009 22:46:14 -0700, DarkSucker
<DarkSucker@thebigbarattheendoftheuniverse.org> wrote:

On Sat, 08 Aug 2009 00:09:56 -0500, krw <krw@att.bizzzzzzzzzzz> wrote:

On Fri, 07 Aug 2009 21:27:42 -0700, StickThatInYourPipeAndSmokeIt
Zarathustra@thusspoke.org> wrote:

On Fri, 07 Aug 2009 23:13:27 -0500, krw <krw@att.bizzzzzzzzzzz> wrote:

On Fri, 07 Aug 2009 20:55:02 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Sat, 08 Aug 2009 03:47:11 GMT, "John KD5YI"
groups2_dot_jocjo@xoxy.net> wrote:


"Rich Grise" <richgrise@example.net> wrote in message
newsan.2009.08.07.19.14.42.685782@example.net...
On Thu, 06 Aug 2009 17:19:44 +0000, John KD5YI wrote:
"Jim Thompson" <To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote in
message news:qi6975htdimheq9lkg1lt85f2dtpjiuirf@4ax.com...
Several years ago, as an aside to another thermal question, I asked...

"Brings to mind a thing I've been pondering... what's the thermal
resistance of 3/4" plywood ?"

Never saw a response.

That's because you've got all the smart people plonked. There were at
least a half-dozen good responses, but apparently the sand got in
your eyes.

From http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html
about .13 W/mK is the thermal conductivity. So, about 7.7 mK/W
resistivity.

Thompson is such an asshole, he doesn't really deserve an answer - why
the hell should we do his googling for him?

Thanks,
Rich


Well, first of all, it's not my job to try to decide who deserves an answer
and who does not.

Second, I find that I learn things by trying to help others. So, it's
somewhat of a selfish motive, I guess.

You're welcome,
John

Aaaaah! Life is wonderful... I've been promoted to "asshole"! Are
there grades of "asshole", like "lieutenant asshole", or "rear admiral
asshole"... ?

Sure, many of us are privates, but there are also general assholes,
like Slowman and DimBulb. ...and of course, the leftist fairies'
assholes aren't private at all.


No I'm an Admiral.

Now, AlwaysWrong, there is nothing admiral about you.

You? You are like that of a sunspot on my dim bulb. That is the level
of your existence. A thermal void.

Your bulb is so dim even the sun won't light it.


No. I absorb the dark, leaving behind only light...

Dogs, you are so very really good at being AlwaysWrong.

 

[Spehro Pefhany]

On Fri, 07 Aug 2009 05:12:47 -0700, the renowned John Larkin
<jjSNIPlarkin@highTHISlandtechnology.com> wrote:

On Thu, 06 Aug 2009 22:29:22 -0700, Archimedes' Lever
OneBigLever@InfiniteSeries.Org> wrote:



Use big nylon nuts and bolts. Or glass filled epoxy.

Which don't conduct electricity very well.

John


You do not have to rely on the fasteners to provide the conduction path
between two mating surfaces. In fact, you shouldn't.

I thought you were talking about thermal conduction anyway.

I was talking about the thermal conductivity of electrical conductors.
The same electrons that transport current also transport heat - pretty
much - so most metals are the same as regards how much current you can
carry for a given heat loss. This matters for stuff like getting power
into a crystal oven or a cryogenic gadget, where we really don't want
the heat loss through the leads.

People use stainless and manganin wire to run to really cold (liquid
helium) gadgets so as to not leak too much heat. Google "Garwin
thermal integral" for some messy math.

John

We also use phosphor-bronze alloy, but I think its main advantage is
high electrical resisitivity (while still being reasonable to handle),
and thus low thermal conductivity, rather than a deviation from the
theoretical (Lorenz) proportionality. IOW, electrically and thermally
it just behaves as a very (impractically) thin copper wire.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Michael A. Terrell]

Joel Koltner wrote:

I'm not generally a fan of unions, but in this particular anecdote, there's
nothing that suggests to me that the guy's experience would necessarily have
been better if unions were *not* involved: If the folks working at Walter Reed
hospital allowed veterans -- who deserve nothing but respect for serving their
country -- to fester in a place with mold, vermin, no hot water, and
incompetent workers, to me it's clear that poor management can happen at any
hospital, regardless or whether or not the workers are civilians or military,
unionized or not.

A lot of the problems at Walter Reed, other military and VA facilities
is that their budgets for renovations & expansions weren't approved.
Instead, the money they needed was spent on political pork projects.
The VA was told to lower their requirements to cover low income Veterans
without access to other medical care about ten years ago. All of a
sudden they were faced with a 200% increase in eligible Veterans, along
with all the retirees covered by 'Tri-care for life'.

The Gainesville VA hospital is quite outdated, but clean. Some areas
look to have been built in the '50s or early '60s. They fought for
almost 15 years to add more patient beds, and for space for modern
equipment. The MRI & Ultrasound department is underground, off the side
of a service tunnel that connects them to Shands Hospital, which is
across a busy highway. Some of the other labs & clinics are scattered
around Gainesville, because there isn't enough room to house them.

The contractor that makes eye glasses was literally stuck in what had
been a closet for cleaning supplies. There wasn't enough parking, but
now that construction has finally started, over half of that is gone.
One part was used for the new patient tower, while the building
contractors are using most of what was left. So, either yo get there
before 6:00 am, or look for a spot on the rented parking lots and hope
the shuttle bus gets you to the hospital in time for your appointment.
They are waiting to hear if the proposed parking garage is approved, and
built. Luckily for me they didn't take away the handicapped parking
area so when I have to drive, there is usually a spot open.

When you consider that the majority of VA patients are over 55, or
severely disabled they need the space. Most of the clinics had to move
the waiting areas out into the hallways, to use the extra space to see
patients. As far as incompetent help, the VA and military have the same
problems as any other hospital. Then you have to add in the Federal
mandates that they have to hire some hard core unemployables for
housekeeping, and other zero skilled jobs.

Walter Reed and other government medical buildings deteriorated as
the patient loads went up faster than their budgets. They had to chose
whether to spend money on the buildings, or let people die.

The local VA clinics were so overloaded that they had to open a
temporary clinic in between. It is to be replaced with a permanent
facility about three times the current size so they can add X-ray and
some other equipment that currently isn't available outside the
hospital. The lease is about up on the clinic I use. The VA wanted to
build a new building tailored to treating elderly & disabled patients,
before Obama took office. I haven't heard another word, since then.
The leased space is on two floors, and most of the time the elevators
are locked out. This forces people to risk falling down the stairs, or
having to walk around the building, to the lower entrance. That is a
ten minute walk, if you're in good health.




--
You can't have a sense of humor, if you have no sense!

 

[Ouroboros Rex]

flipper wrote:

On Tue, 11 Aug 2009 10:46:18 -0500, "Ouroboros Rex" <its@casual.com
wrote:

flipper wrote:
On Mon, 10 Aug 2009 09:27:07 -0500, "Ouroboros Rex" <its@casual.com
wrote:

flipper wrote:
On Sun, 9 Aug 2009 14:31:19 -0500, "Ouroboros Rex"
its@casual.com> wrote:

flipper wrote:
On Fri, 7 Aug 2009 10:38:33 -0500, "Ouroboros Rex"
its@casual.com> wrote:

Jim Thompson wrote:
http://hotair.com/archives/2009/08/06/white-house-to-dems-on-town-halls-if-you-get-hit-we-will-punch-back-twice-as-hard/

Sorry, lying right wing editorial. The fact is that the
AFL-CIO took it's own initiative.

My hope is that the lying astroturfers carrying around signs
with swastikas and gravestones andhanging congressmen in effigy
get exactly what they deserve.

They're just recycled swastikas and effigies from the 'Bush is a
NAZI' campaign. Gee, I thought recycling was supposed to be a
good thing and plagiarism is the sincerest form of flattery.

Aren't you proud?

They started it

The left did and it's rank hypocrisy on the left's part to
complain about others using their exact same tactics.

What you mean is, you can't find any examples of the left using
the exact same tacits in a town hall meeting.


ROTFLOL

No, I mean the left uses those tactics any time there are more
than two people in any one place.

cuckoo cuckoo cuckoo

I know you are.


Aren't you proud?

Sounds like your conversation isn't suited to off-topic use of a
worldwide forum, privacy-wise - maybe you should start a
yahoogroup. =)

You're still unable to comprehend a simple three word question, I
see.


Poor Floppy just can't stop trying to change the subject. lol

You're the one who's trying to change it, as witnessed by your
continued inability to answer a simple 3 word question.


The left did and it's rank hypocrisy on the left's part to
complain about others using their exact same tactics.

What you mean is, you can't find any examples of the left using
the exact same [tactics] in a town hall meeting.

Keep running.

 

[Ouroboros Rex]

flipper wrote:

On Tue, 11 Aug 2009 13:41:49 -0500, "Ouroboros Rex" <its@casual.com
wrote:

flipper wrote:
On Mon, 10 Aug 2009 09:35:40 -0500, "Ouroboros Rex" <its@casual.com
wrote:

flipper wrote:
On Sun, 9 Aug 2009 14:33:25 -0500, "Ouroboros Rex"
its@casual.com> wrote:

flipper wrote:
On Fri, 7 Aug 2009 09:59:19 -0500, "Ouroboros Rex"
its@casual.com> wrote:

flipper wrote:
On Thu, 6 Aug 2009 09:31:56 -0500, "Ouroboros Rex"
its@casual.com> wrote:

flipper wrote:
On Wed, 5 Aug 2009 11:43:27 -0500, "Ouroboros Rex"
its@casual.com> wrote:

Jim Thompson wrote:
This will send a chill down your spine...

http://www.whitehouse.gov/blog/Facts-Are-Stubborn-Things/

Big brother is watching... big time :-(

Bullshit.

"There is a lot of disinformation about health insurance
reform out there, spanning from control of personal
finances to end of life care. These rumors often travel
just below the surface via chain emails or through casual
conversation. Since we can't keep track of all of them
here at the White House, we're asking for your help. If
you get an email or see something on the web about health
insurance reform that seems fishy, send it to
flag@whitehouse.gov."

You are such a good little mind numbed robot.

When, in the immediate aftermath of 9/11, the Bush
Administration asked the public to keep an eye out for
potentially life threatening, illegal, terrorist activity
and report same to the appropriate authorities the left
went into an apoplectic fit screaming fascist, fascist, but
you think it's perfectly fine for people to collect and
send private communications to the White House for nothing
more threatening than expressing a political opinion Obama
doesn't like.

Let's see, the left says reporting life threatening illegal
activities bad.

Bullshit.

and the left is full of it.


Hate to burst your fascist bubble but the First Amendment
doesn't say only speech Obama likes, or only speech you
like, or only speech Obama deems politically appropriate or
only speech Obama, in his great wisdom. deems the one and
only 'truth'. It protects SPEECH.

Only a complete idiot would think this is for anything but
rebuttal. lol

Frankly, my dear, I don't give a flying fig *what* your
twisted little swastika imagines the 'purpose' to be. It's a
violation of both free speech and privacy rights,

Pathetic lie.

Spoken like a good loyal fascist.

What you mean is, you can't find proof one for your lie above.
lol


regardless, and the Constitution makes no
exceptions for "unless the Obama administration finds
infringing on these rights convenient for stomping on it's
political opposition" nor is there one for 'convenient
rebuttal'.

But, since liberals don't give a dam what the Constitution
says, I feel compelled to point out it's also illegal by
statute passed by a Democrat Congress.

Pathetic lie.

ditto

What you mean is, you can't find proof one for your lie above.
lol


And, as I already mentioned in the parts you dishonestly
snipped, all of it is readily available on the Internet
ranging from 'mainstream' new sources, to editorials, to
blogs, to youtube and the only schmucks apparently not only
deaf dumb and blind to the deluge of concern but unable to
google and click on a link to inform themselves are Mr.
Teachable Moment and his 'communications director'.

Pathetic lie.

ditto

What you mean is, you can't find proof one for your lie above.
lol



What I mean is exactly what I said. You speak like a good loyal
fascist.

More nothing from the nothng.


So you being a fascist is "nothing."

You speak like a good loyal fascist.

More nothing from the nothing.


Spoken like a good loyal fascist.

"RUN AWAY, RUN AWAY," screamed floppy. "Here, I'll change the subject to
the poster so I don't have to back up my lies! Then I'll keep repeating a
braindead pig-ignorant accusation of 'fascism' and my braindead friends will
think it's a response!"

<snicker>

 

[John Larkin]

On Wed, 12 Aug 2009 05:11:19 -0700,
"JosephKK"<quiettechblue@yahoo.com> wrote:

On Fri, 07 Aug 2009 05:12:47 -0700, John Larkin
jjSNIPlarkin@highTHISlandtechnology.com> wrote:

On Thu, 06 Aug 2009 22:29:22 -0700, Archimedes' Lever
OneBigLever@InfiniteSeries.Org> wrote:



Use big nylon nuts and bolts. Or glass filled epoxy.

Which don't conduct electricity very well.

John


You do not have to rely on the fasteners to provide the conduction path
between two mating surfaces. In fact, you shouldn't.

I thought you were talking about thermal conduction anyway.

I was talking about the thermal conductivity of electrical conductors.
The same electrons that transport current also transport heat - pretty
much - so most metals are the same as regards how much current you can
carry for a given heat loss. This matters for stuff like getting power
into a crystal oven or a cryogenic gadget, where we really don't want
the heat loss through the leads.

People use stainless and manganin wire to run to really cold (liquid
helium) gadgets so as to not leak too much heat. Google "Garwin
thermal integral" for some messy math.

John

And google John Larkin for occasional very sloppy math/physics/units.

Cite?

Do you think that characterizing a material for thermal resistance per
ohm of electrical resistance is somehow "sloppy"? Or maybe a mortal
sin? I've found the concept to be useful a number of times. The cryo
folks deal with this all the time.

All sorts of metrics can be fun, like transformer watts per pound [1],
degress C per foot of altitude, dollar value of Virtex FPGAs per cubic
meter, raindrops per square mile per second, stuff like that. I
suppose you'd disapprove of the associated engineering units.

Come on, quit being so Slomanesque and have a little fun with math.

John

[1] Grab a couple of catalogs and do a scatter graph on that one.
Interesting, at least for people who find things interesting.

 

[John Larkin]

On Wed, 12 Aug 2009 05:05:33 -0700,
"JosephKK"<quiettechblue@yahoo.com> wrote:

On Wed, 05 Aug 2009 21:18:51 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Wed, 05 Aug 2009 20:57:04 -0700,
"JosephKK"<quiettechblue@yahoo.com> wrote:

On Sun, 02 Aug 2009 17:25:17 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sun, 02 Aug 2009 16:45:07 -0700, Robert Baer
robertbaer@localnet.com> wrote:

John Larkin wrote:

snip

Ahh.. that is what someone else implied and did *not* specify.
But since i am not into thermal conductivity and/or insulation, the
"meter" does not make sense to me in this context.
Would have to dig into this usage and the units.

Thermal conductivity, in SI units, is specified in watts per
meter-Kelvin.

Aluminum is about 240 w/m-K.

So if you had a 1-meter cube of the stuff, and forced a 1 degree C
difference across opposite faces, 240 watts of heat would flow.

The thermal resistance would be the reciprocal, about 0.004 degrees C
per watt.

Starting from there, it's easy to scale for area and thickness.

Fun fact: the thermal resistance of copper is about 150,000 degs C per
watt per ohm.

The standard unit of thermal conductivity (inverse of thermal
resistance) is W/(m*K), no "ohms" involved. So much for your "fun
fact"

What a doofus you are determined to be. One can certainly define a
material property Z = thermal conductivity per ohm of electrical
resistance. For most pure metals, it's about 150,000 (K/W)/ohm.

Among other things, it's a quick way to convert wire tables into
values of thermal resistance for copper wires or rods.

QED

What you're proving is how rigid your thinking is constrained by
"standard units." Lighten up a little.

John

 

[Ouroboros Rex]

UltimatePatriot wrote:

On Tue, 11 Aug 2009 13:40:52 -0500, "Ouroboros Rex" <its@casual.com
wrote:

UltimatePatriot wrote:
On Mon, 10 Aug 2009 09:38:37 -0500, "Ouroboros Rex" <its@casual.com
wrote:

UltimatePatriot wrote:
On Sun, 9 Aug 2009 14:32:31 -0500, "Ouroboros Rex"
its@casual.com> wrote:

You mean trespassing.

How does showing up at a public forum equate to trespassing, you
retarded little unamerican piece of shit?

They just showed up and waited to get in, did they? Cite please.

Where did you see it written that that was the procedure?

You really are one retarded motherfucker, pussy boy.


Public lot. Public building. Public forum. Public meeting.

Where is the trespassing at you retarded, pussified lying piece of
shit?

In other words, no cite, just more nothing from the nothing.


Where is the trespassing at you retarded, pussified lying piece of
shit?

Every dumbass who entered the doorway after the building was at capacity
and they had been told they could not enter, 'you retarded, pussified, lying
piece of shit'.

http://www.wtsp.com/video/default.aspx?aid=88418

Continue lying. lol

 

[Joerg]

Michael A. Terrell wrote:

Joerg wrote:
Joel Koltner wrote:
"John Larkin" <jjSNIPlarkin@highTHISlandtechnology.com> wrote in message
news:68go75hnn0vqtbt1svhes90vpohhof84ek@4ax.com...
10 Mbit WiFi works much better than 100 Mbit WiFi.
Just thought I'd point that out.
Something about bandwidth-SNR being constant for a given power, I think

That being said, I've seen several instances where some salesdroid is trying
to upsell little old ladies 802.11n wireless routers when they only have a
couple of computers and only plan to use the router to allow each machine to
access their 1.5Mbps or so Internet connection. Sad.

It can also happen with phones. Sell a "modern" 5GHz system to an
unsuspecting customer and they can't even walk towards the garage
anymore without the phone link breaking up.


I can talk over 100 feet from the base station with my 5.8 GHz phone
even though there is a building with aluminum siding between me and my
mail box, and the base is inside another building with aluminum siding.

Sometimes you can get lucky and there are reflections from other objects
to make up for a low signal situation. In this house here (aluminum
backed insulation in all walls including interior ones) the old rule
applies. The lower the frequency the better stuff works.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

 

[Skybuck Flying]

You foreingers do have social wellfare right ?

(Like USA?)

Bye,
Skybuck

"Skybuck Flying" <BloodyShame@hotmail.com> wrote in message
news:c68c0$4a800023$d53372a9$4599@cache2.tilbu1.nb.home.nl...

Hello,

For as far as I understand there was once a world where artist and so
would live in the gutter because they couldn't earn money with their
work/hobby/passion.

That world is long gone thanks to social wellfair.

Being an artist is about createn art and that sort of works because you do
it with love, with passion, because you enjoy it, or find it
interesting... and not because to get filthy rich from it.

I say: Scrap the copyrightlaw it's not needed anymore and it will only
create many problems now and in the future !

Scrapping it is necessary to create a pleasent and free information
world/society.

I fear that if this copyrightlaw is not scrapped we will start to slide
further towards a very nasty world !

Also don't work to hard good people, many artist don't as well nowadays...

Only the red copy button is pressed and the rest goes fully automatic ! =D

Be carefull/sparefull with your hard earned cash !

Bye,
Skybuck.

 

[Rich Grise]

On Wed, 12 Aug 2009 07:23:19 -0700, John Larkin wrote:

All sorts of metrics can be fun, like transformer watts per pound [1],

[1] Grab a couple of catalogs and do a scatter graph on that one.
Interesting, at least for people who find things interesting.

This isn't as goofy as it sounds - I've actually used this parameter,
albeit it was spec'd as "volt-amps".

Back in my HAM days (ca. half a century ago), this was mentioned in
more than one article on rewinding surplus transformers. Well, more
like the cross-section of the middle leg of the E, but it translates
quite well into VA/lb. (or lb/VA, depending on your POV.)

In fact, I once had a boss make a fool of himself over this - I was
tasked to spec a replacement transformer, because they'd changed the
requirements for one of the secondaries.

In this box, they had a selector switch to choose one of two secondaries,
but NEVER both (DPDT Switch); and I only had to change one, and the VA
didn't change much. The moron boss overrode me and spec'd it as if BOTH
secondaries would be running at once, which they were guaranteed (in this
box) to never do.

This was a retrofit, i.e., an ECO.

The new tranny came in and it didn't even fit in the original box! I
almost felt bad for the guy, he was so embarrassed, but I secretly gloated
inside because the guy was like The Fourth Stooge - worse than Dilbert's
PHB.

After I got myself fired and collected a few months' unemployment, I got
a new job, which was about the best job I'd ever had, and at the new
company, I ran into two - count'em - TWO former co-workers who had worked
under TFS. ;-)

Thanks!
Rich

 

[Rich Grise]

On Wed, 12 Aug 2009 08:53:38 -0400, Spehro Pefhany wrote:

On Fri, 07 Aug 2009 05:12:47 -0700, the renowned John Larkin

People use stainless and manganin wire to run to really cold (liquid
helium) gadgets so as to not leak too much heat.

I thought this was because they stand up to the cryo temps better than
other alloys.

Google "Garwin
thermal integral" for some messy math.

We also use phosphor-bronze alloy, but I think its main advantage is
high electrical resisitivity (while still being reasonable to handle),
and thus low thermal conductivity, rather than a deviation from the
theoretical (Lorenz) proportionality. IOW, electrically and thermally
it just behaves as a very (impractically) thin copper wire.

This (thermal :: electrical) kinda breaks down with diamond. ;-)

Cheers!
Rich

 

[Spehro Pefhany]

On Wed, 12 Aug 2009 18:13:29 GMT, Rich Grise <richgrise@example.net>
wrote:

On Wed, 12 Aug 2009 08:53:38 -0400, Spehro Pefhany wrote:
On Fri, 07 Aug 2009 05:12:47 -0700, the renowned John Larkin

People use stainless and manganin wire to run to really cold (liquid
helium) gadgets so as to not leak too much heat.

I thought this was because they stand up to the cryo temps better than
other alloys.

No, 4K doesn't really hurt most materials.

Strength vs. thermal conductivity is an interesting ratio too. Very
important for constructing hot runner injection molds where you have
hundreds of degrees temperature differential and rather large forces
(that cycle every few seconds).

Google "Garwin
thermal integral" for some messy math.

We also use phosphor-bronze alloy, but I think its main advantage is
high electrical resisitivity (while still being reasonable to handle),
and thus low thermal conductivity, rather than a deviation from the
theoretical (Lorenz) proportionality. IOW, electrically and thermally
it just behaves as a very (impractically) thin copper wire.


This (thermal :: electrical) kinda breaks down with diamond. ;-)

Since when is diamond a metal?

 

(abse dropped, for GoogleGroups)
On Aug 9, 8:34 pm, flipper <flip...@fish.net> wrote:

On Sun, 9 Aug 2009 14:32:31 -0500, "Ouroboros Rex" <i...@casual.com
wrote:

UltimatePatriot wrote:
On Fri, 7 Aug 2009 14:17:24 -0500, "Ouroboros Rex" <i...@casual.com
wrote:

There were at least two scuffles between protesters trying to enter
and organizers manning the doors.

 Looks more to me like the retards at the door provoked the response
by way of their illicit act of attempting to stop citizens from
entering a public forum.

 You mean trespassing.

Spoken like a good loyal fascist: "No dissent allowed."

Oddly, "community organizing" becomes "nazi astroturfing" when your
opponents do it, even if they've a majority.

Cheers,
James Arthur

 

[Les Cargill]

clare@snyder.on.ca wrote:

On Mon, 10 Aug 2009 20:50:17 -0600, "Don T" <-painter-@louvre.org
wrote:

clare@snyder.on.ca> wrote in message
news:jck18590grpni0bvkf4jgqd1sujh97edc1@4ax.com...
On Mon, 10 Aug 2009 17:45:42 -0600, "Don T" <-painter-@louvre.org
wrote:

"daestrom" <daestrom@twcny.rr.com> wrote in message
news:h5q7en12lar@news2.newsguy.com...
Don T wrote:
"Richardson" <member@newsguy.com> wrote in message
news:JYWdncZmtr_K2uPXnZ2dnUVZ_tOdnZ2d@posted.toastnet...

Again power is not measured in AMP, but in WATT you stupid jerks, Give
it
up now suckers.

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


If you know it all answer me this. Why are tools like electric drills
and
even shop vacuums listed as having 6.0 AMP etc. motors?

http://www.blackanddecker.com/ProductGuide/CategoryOverview.aspx?cPath=1496.2050

Because it makes better advertising copy than 0.48 horsepower??

daestrom
=> snicker <=

Probable, but it makes the statement that "power is never measured in
ampere units" quite wrong.

The 6 amp motor means it draws 6 amps from the mains. It does not mean
ANYTHING as far as how much power it produces, other than that it
cannot produce more than 690 watts at 115 volts
I know exactly what it means. I also know that corded tools in the USA are
rated in amps these days. I even provided a random link to demonstrate that
FACT. So whether you or richardson claim it is never done I have
demonstrated that it IS done. An apology would be asking too much so just
accept that you have been successfully refuted and let it go at that.


Yes, tools are advertised and rated in North AAMerica by their
Amperage. This is, however, NOT power. It is advertizing gobbledegook.
It is "dumbed down" specifications.

Nah. It's how electrical service is specified in the US.

If you have 30 amps worth of stuff on a 15 amp breaker,
the breaker will flip.

--
Les Cargill

 

[Les Cargill]

miso@sushi.com wrote:

On Aug 8, 2:13 pm, "Joel Koltner" <zapwireDASHgro...@yahoo.com> wrote:
"John Larkin" <jjSNIPlar...@highTHISlandtechnology.com> wrote in message

news:68go75hnn0vqtbt1svhes90vpohhof84ek@4ax.com...

10 Mbit WiFi works much better than 100 Mbit WiFi.
Just thought I'd point that out.
Something about bandwidth-SNR being constant for a given power, I think

That being said, I've seen several instances where some salesdroid is trying
to upsell little old ladies 802.11n wireless routers when they only have a
couple of computers and only plan to use the router to allow each machine to
access their 1.5Mbps or so Internet connection. Sad.

I think the Shannon theorem comes to play here. However, the 100Mbps
wifi falls back to the slower standards, right? Now sometimes when
fallback modes are put in comm gear, the quality of the fallback
design is poor. That is, someone is addressing a marketing bullet
point rather than designing a robust system.

The fallbacks in Wifi are pretty high quality. It's not exactly
bleeding edge any more. Link layer is mostly in chipsets,
give or take.

In the dark ages when I worked on a 2400bps analog modem, we satisfied
fallback to a stupidly good degree of quality, but only because it
wasn't very difficult. For instance, the FSK fallback was done with a
coordic computing arcsin to phase unwrap the signal, then a running
LMS fit to determine frequency. Insane quality, but all the routines
were present for other uses in the target application.

Back to wifi, if you war drive, generally you notice the data rate is
down to 1Mbps, presumably due to a more robust (noise tolerant)
communications scheme.

--
Les Cargill

 

[Richard Henry]

On Aug 7, 8:55 pm, Jim Thompson <To-Email-Use-The-Envelope-I...@My-Web-
Site.com> wrote:

On Sat, 08 Aug 2009 03:47:11 GMT, "John KD5YI"



groups2_dot_jo...@xoxy.net> wrote:

"Rich Grise" <richgr...@example.net> wrote in message
newsan.2009.08.07.19.14.42.685782@example.net...
On Thu, 06 Aug 2009 17:19:44 +0000, John KD5YI wrote:
"Jim Thompson" <To-Email-Use-The-Envelope-I...@My-Web-Site.com> wrote in
messagenews:qi6975htdimheq9lkg1lt85f2dtpjiuirf@4ax.com...
Several years ago, as an aside to another thermal question, I asked....

"Brings to mind a thing I've been pondering... what's the thermal
resistance of 3/4" plywood ?"

Never saw a response.

That's because you've got all the smart people plonked. There were at
least a half-dozen good responses, but apparently the sand got in
your eyes.

Fromhttp://www.engineeringtoolbox.com/thermal-conductivity-d_429.html
about .13 W/mK is the thermal conductivity. So, about 7.7 mK/W
resistivity.

Thompson is such an asshole, he doesn't really deserve an answer - why
the hell should we do his googling for him?

Thanks,
Rich

Well, first of all, it's not my job to try to decide who deserves an answer
and who does not.

Second, I find that I learn things by trying to help others. So, it's
somewhat of a selfish motive, I guess.

You're welcome,
John

Aaaaah!  Life is wonderful... I've been promoted to "asshole"!  Are
there grades of "asshole", like "lieutenant asshole", or "rear admiral
asshole"... ?

You are only a major asshole.