magnetic field

chibitul · Sep 29, 2004

In article <MPG.1975a4a8df351800989a51@news.inreach.net>,
Watson A.Name - 'Watt Sun' <alondra101@hotmail.com> wrote:

In article <ch1b1tul-71CB01.23171206072003@newssvr10-
ext.news.prodigy.com>, ch1b1tul@sbcglobal.net mentioned...
hi,

Not sure if this is the right newsgroup, but here it goes anyway:

Probably not.

[snip]

and now the tech savvy question: how does it work? is it magnetic? if
so, why can't shoplifters use a magnet to demagnetize it??? if it's not
magnetic, what is it???

Ask the company, it's Knogo.

I know some of them can be re-activated somehow, they did this in the
library back at university: when you check out a book they de-activate
it, when you return the book they activate it again.

The library uses one that's not the same.

magnetic??? something else??? curiuos, but more important, please I need
a solution for that purse

I think you are fishing for info on how to defeat their system.

OK, give me your address, I will ship you the purse. moron...

Richard Crowley · Sep 29, 2004

"alexandre semedo" wrote ...

I don't know if this group is the correct one for my question.
I'm searching for a small screen to attach to a computer using
paralell/serial or radio link (distance is at least 15 meters) for
viewing at least two numbers(digits) at a distance.
A computer language will send the information to the device.

If anyone knows of a comercial implementation of this i would be
very grateful.

http://www.electronicdisplays.com/
almost certainly several others

FEerguy9 · Sep 29, 2004

"FEerguy9" <feerguy9@cs.com> wrote in message
news:20030711013635.14767.00000164@mb-m07.news.cs.com...

I had neither unification theory nor multiple dimensions in mind.
Further, I
do not see why you brought them up.

If extra dimension exist then they extreemly tightly curled up (or we would
be able to detect them easily) so I guess you might be able make (something
like) a capacitor that stores (something like) charge in these extra
dimensions. Perhaps that might be a way round the problem that the breakdown
voltage is proportional to plate seperatiion - after all it's quite possible
for objects to be close together in some dimensions yet far apart in others.

Plain and simple - I am talking about the space betweer the surface of a
capacitor plate, and the molecular level.

Perhaps you made a typo and meant "_at_ the molecular level"?.

OK

. but thats also confusing. Every space exists "at the molecular level" even
large
spaces. It would be better to use SI units.

If you are talking about reducing the plate seperation until it's less than
a molecule wide then that's something we can discuss...

<--not thinking that it would be necessary to go that small.

A water molecule is about 3 x 10^-10 Meters wide (not that you would use
water obviously but it gives us sense of scale). How about using "Strontium
Titanate" ?. If I understand correctly that breaks down at about 8MV/M
(8,000,000 Volts per Meter). I don't know how big a Strontium Titanate
molecule is but lets assume it's the same size as a water molecule (it's
bigger) and that it still behaves like a dielectric in such thin layers
(unlikely)... we'll press on and make a capacitor with a plate seperation of
3 x 10^-10M. Having done that lets calculate what the max working voltage
would be....

Vmax = 8x10^6 x 3x10^-10 or about 24x10-4 = 2.4mV.

If you charge your capacitor beyond 2.4 milivolt the dielectric will fail.

I suggested low voltage, until dielectrics get better.

Oh dear not going to be much use is it?

Let's ignore that and the fact that things behave differently at the Quantum
scale... If the gap was reduced further you wouldn't be able to fit a
molecule of anything between the plates and you would have to use a vacuum.
That ok if you can keep the plates apart somehow? Lets reduce it further to
the atomic scale - say less than the diameter of a metal atom - At this
distance the plates are so close together that in effect they are one lump
of metal and electrons flow freely between them. eg our capacitor is now a
short circuit so that sets a lower limit.

Now what seperation do you propose exactly?

Very small - as small as the dielectric will allow.

CWatters · Sep 29, 2004

"FEerguy9" <feerguy9@cs.com> wrote in message
news:20030713043642.26547.00000276@mb-m18.news.cs.com...

Now what seperation do you propose exactly?

Very small - as small as the dielectric will allow.

Now we have you going in circles for a change.

Christopher Klassen · Sep 29, 2004

you know, these sites aren't really the place for your discussion.....maybe
you could try "alt.semantics.whiners.name-calling"? If it doesn't exist, you
could always make it up....leave these sites for people actually discussing
the intended topics, please.

-Chris

"DarkMatter" <DarkMatter@thebarattheendoftheuniverse.org> wrote in message
news:gtcpgvkq8oath4aqr980uboeoi0dier69b@4ax.com...

On Wed, 09 Jul 2003 06:04:41 GMT, Bucephalis <xsglynn@yahoo.com> Gave
us:

There is a big difference between protocol and etiquette, obvious
idiot.
Only in spelling.

More proof of your total cluelessness.

Rich Grise · Sep 29, 2004

Some of us "idiots" top post in hopes that our contribution will actually
get read. If somebody's bottom posted at the bottom of a post that
they've quoted in its entirety, I usually just skip it, having read
that particular post a dozen times already in the thread.

Then there's mid-posting, where each pertinent point is addressed
individually. But this is probably too advanced of a concept. I guess
I like my audience to be my intellectual equal. This is somewhat
akin to finding one specific grain of sand in the Sahara desert,
and you can't even use a magnet. (maybe a lantern...)

So, if you don't like top-posting, don't read the posts. I skip
over bottom-posts, unless the poster has judiciously excised
extraneous material.

Cheers!
Rich

Now, you see, you're free to read the background of the post at
your leisure -

"Larry" <nospam@sorry.wishididnhaveto.com> wrote in message news:<3f006cde$1_3@corp.newsgroups.com>...

"Idiots" huh?

I believe that name calling also violates the Usenet etiquette rules which
pretty much cancels out your opinion on the matter. Top posted for your
pleasure...

Larry

"DarkMatter" <DarkMatter@thebarattheendoftheuniverse.org> wrote in message
news:mliufv0filab6v6rfnmtjk4ku5omdnipoc@4ax.com...
On Fri, 27 Jun 2003 22:51:51 GMT, "C what I mean" <pythan@pacbell.net
Gave us:

LOL!!!

Why do all you idiots top post? This is usenet. I mean, I know
that it is easy to follow Bill and his stupidity with Outlook and
Outlook Express, but people please... BONE UP on usenet posting
protocols.

DarkMatter · Sep 29, 2004

On Sun, 13 Jul 2003 14:46:20 GMT, "Christopher Klassen"
<klascs@telusplanet.net> Gave us:

you know, these sites aren't really the place for your discussion.....maybe
you could try "alt.semantics.whiners.name-calling"? If it doesn't exist, you
could always make it up....leave these sites for people actually discussing
the intended topics, please.

More top posted bullshit from an idiot that has absolutely no clue
about usenet. Regardless of the discussions, your blatant ignorance
of posting protocols makes you the exact retard I said that you are...
It is true. You are that retard. Look the word up, ditz boy.

As far as telling me where to post... Fuck you.

As far as me telling you HOW to post.. . an entirely different
animal, you retarded putz!

Watson A.Name - 'Watt Sun · Sep 29, 2004

In article <njv3hv4lbgg79b7461t9ps2d2tfoktt5f2@4ax.com>,
DarkMatter@thebarattheendoftheuniverse.org mentioned...

On 13 Jul 2003 13:11:35 -0700, richardgrise@yahoo.com (Rich Grise)
Gave us:

Some of us "idiots" top post in hopes that our contribution will actually
get read.

That remark proves that you have no clue about usenet, and think
that everyone reads usenet from within Billy boy's lame Outlook
express reader. You are retarded to the Nth degree. Bone up on the
FACTs, dipshit.

If somebody's bottom posted at the bottom of a post that
they've quoted in its entirety, I usually just skip it, having read
that particular post a dozen times already in the thread.

That is because you ARE a usenet retard!

Then there's mid-posting, where each pertinent point is addressed
individually. But this is probably too advanced of a concept. I guess
I like my audience to be my intellectual equal. This is somewhat
akin to finding one specific grain of sand in the Sahara desert,
and you can't even use a magnet. (maybe a lantern...)

You are an idiot. The posts are NOT for YOU. Usenet is a message
board format. The post could be read ages later, you twit.
Chronological posting is needed so that a person can read the post,
and get the gist LATER on down the line, you clueless ditz.

So, if you don't like top-posting, don't read the posts. I skip
over bottom-posts, unless the poster has judiciously excised
extraneous material.

YOU are a usenet retard. E-1 grade, at best. You are like the data
entry twits that took the job, but don't know what cursor keys are
for! You epitomize usenet stupidity to the Nth degree!

And you're just as bad, if not worse. Like we need your
'constructive' criticism. FURRFU...

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@

DarkMatter · Sep 29, 2004

On Sun, 13 Jul 2003 18:09:08 -0700, Watson A.Name - 'Watt Sun'
<alondra101@hotmail.com> Gave us:

And you're just as bad, if not worse. Like we need your
'constructive' criticism. FURRFU...

FOAD, jackass. I am calling them idiots, because they are just
that. It has nothing to do with being "constructive" Hell, I'd throw
all yer lame asses in the "no access pit", if I could. None of you
have enough brains to follow the protocols, because none of you had
brains enough to learn about the forum in which you spew in the first
place. You are little mosh pit, "rules are meant to be broken" punk
retards, at best. You take the time to learn something technical, but
dismiss any modicum of standards conformance whenever it suits you.
Fuck you all, you retarded twits.

You are like cigarettes smokers that throw their butts on the
ground. For everyone else, it is littering. For the wussy smoker, it
is "perfectly fine behavior".

A working class hero is something to be, but you are still fucking
peasants as far as I can see. -John Lennon.

Bone up on Usenet, ya retarded idiots!

Christopher Klassen · Sep 29, 2004

Thus spake "DarkMatter" <DarkMatter@thebarattheendoftheuniverse.org> in
message news:sfm4hvgdj7ut8gvoj01hcu6ol23r0k4hc2@4ax.com...

FOAD, jackass. I am calling them idiots, because they are just
that. It has nothing to do with being "constructive" Hell, I'd throw
all yer lame asses in the "no access pit", if I could. None of you
have enough brains to follow the protocols, because none of you had
brains enough to learn about the forum in which you spew in the first
place. You are little mosh pit, "rules are meant to be broken" punk
retards, at best. You take the time to learn something technical, but
dismiss any modicum of standards conformance whenever it suits you.
Fuck you all, you retarded twits.

You are like cigarettes smokers that throw their butts on the
ground. For everyone else, it is littering. For the wussy smoker, it
is "perfectly fine behavior".

A working class hero is something to be, but you are still fucking
peasants as far as I can see. -John Lennon.

Bone up on Usenet, ya retarded idiots!

"little mosh pit, 'rules are meant to be broken' punk retards," eh? How old
are you . . . 12? You know, the way you rant, and have to use vulgarities
to cover up your lack of a better-than-grade-six vocabulary makes your
arguments fall a little short. Thank goodness my "lame Outlook Express
reader" has the "block sender" function so I need not waste any more time on
you, and can concentrate on reading posts about *gasp* high-voltage
electronics!

-chris

PS - sorry to the rest of you for wasting your time. this will be my last
post to DM's inane prattle. (look it up, DM)
CK

Jim Thompson · Sep 29, 2004

On Mon, 14 Jul 2003 14:06:24 GMT, "Christopher Klassen"
<klascs@telusplanet.net> wrote:

Thus spake "DarkMatter" <DarkMatter@thebarattheendoftheuniverse.org> in
message news:sfm4hvgdj7ut8gvoj01hcu6ol23r0k4hc2@4ax.com...

FOAD, jackass. I am calling them idiots, because they are just
[snip]

"little mosh pit, 'rules are meant to be broken' punk retards," eh? How old
are you . . . 12? You know, the way you rant, and have to use vulgarities
to cover up your lack of a better-than-grade-six vocabulary makes your
arguments fall a little short. Thank goodness my "lame Outlook Express
reader" has the "block sender" function so I need not waste any more time on
you, and can concentrate on reading posts about *gasp* high-voltage
electronics!

-chris

PS - sorry to the rest of you for wasting your time. this will be my last
post to DM's inane prattle. (look it up, DM)
CK

480)460-2350 | |
| Jim-T@analog_innovations.com Fax

Dave · Sep 29, 2004

Howdy,

Well I have the same motor and I think you may encounter a probably in trying
to stop it at specific steps. The motor controller I use changes the speed and
allows
me to alter the speed range but no matter what speed it is running at the motor
will
coast for a short period of time until it reaches a lower speed. I think if you
want it
to stop at several specific points you may have to use some kind of electric
clutch.

Somehow you have to have the lift disengage from the motor drive to overcome the

coasting effect of the DC motor.

Is this any help?

dirwi@execulink.com

wanton wrote:

Hi - I am the proud new owner of a 90V Leeson DC 1/4hp motor and KB
electronics control for fun and hobby. I'm really green about this stuff
and I need some info for safety reasons.

The Project: I want to use the motor to make a lift that will go up and down
and stop at any point in between.

The controller manual says I can perform rapid switching on the AC inputs
without damaging anything. Although, It says I cannot perform this with the
DC outputs - else I can expect catastrophic results - whatever those would
be. OK, then without having to purchase a different controller how do I
make this controller work? I need the motor to go CW and CCW using
hopefully a rocker switch of some sort. Sounds like I might have to have 2
switches, one for the AC on/off and one to toggle the DC polarity when the
AC is off. Sure would be nice to only use one rocker switch though.

Regarding safety, do I need to mount the switches in a special box or have
specially rated switches, etc.? I don't want to get bit.

Any help is appreciated

Andre · Sep 29, 2004

NightRunner <jackfrostnippin@yernose.com> wrote in message news:<mdb4gvc4r02iui0h2ggcukmmkgmh00iect@4ax.com>...

Hehehe

It amazes me that a substation could put on such a show, really wild.
I have a whole new respect for high power electrical transmission. And
you know what, when I was a teenager I actually considered breaking
into one of those places to have a close look... Sheeeeesh!

Yeah, those things have the "Danger of Death" warnings for a good reason .

Solar power is much safer . See www.sunnythings.com for ideas

-A

- NR

On Tue, 01 Jul 2003 05:11:57 GMT, Don Bruder <dakidd@sonic.net> was
reportedly seen on the White House lawn holding a large picket sign
and screeching the following:

In article <2c2cf14c.0306261126.1597a8b2@posting.google.com>,
testing_h@yahoo.com (Andre) wrote:

http://205.243.100.155/frames/mpg/XfrmBlast1.mpg

-A

Whoops? WHOOPS??? That'a ALL you can say is "Whoops"????

"The usual approach of science of constructing a mathematical
model cannot answer the questions of why there should be a
universe for the model to describe. Why does the universe go
to all the bother of existing?"

- Stephen Hawking

---------------------------------------
Our Website:
http://niter417.virtualave.net/

Message Boards Main:
http://niter417.virtualave.net/cgi-bin/yabb/YaBB.pl

Laser Discussion:
http://niter417.virtualave.net/cgi-bin/yabb/YaBB.pl?board=Lasers

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http://niter417.virtualave.net/cgi-bin/yabb/YaBB.pl?board=3

Winemaking Discussion:
http://niter417.virtualave.net/cgi-bin/yabb/YaBB.pl?board=8

Our Webcam:
http://web.infoave.net/~missy1/cam/webcam.html

Mark · Sep 29, 2004

"DarkMatter" <DarkMatter@thebarattheendoftheuniverse.org> wrote in message
news:sfm4hvgdj7ut8gvoj01hcu6ol23r0k4hc2@4ax.com...

On Sun, 13 Jul 2003 18:09:08 -0700, Watson A.Name - 'Watt Sun'
alondra101@hotmail.com> Gave us:

And you're just as bad, if not worse. Like we need your
'constructive' criticism. FURRFU...

FOAD, jackass. I am calling them idiots, because they are just
that. It has nothing to do with being "constructive" Hell, I'd throw
all yer lame asses in the "no access pit", if I could. None of you
have enough brains to follow the protocols, because none of you had
brains enough to learn about the forum in which you spew in the first
place. You are little mosh pit, "rules are meant to be broken" punk
retards, at best. You take the time to learn something technical, but
dismiss any modicum of standards conformance whenever it suits you.
Fuck you all, you retarded twits.

You are like cigarettes smokers that throw their butts on the
ground. For everyone else, it is littering. For the wussy smoker, it
is "perfectly fine behavior".

A working class hero is something to be, but you are still fucking
peasants as far as I can see. -John Lennon.

Bone up on Usenet, ya retarded idiots!

Difficult day petal?

Mark

Fred Abse · Sep 29, 2004

On Mon, 14 Jul 2003 18:18:34 +0100, Dave wrote:

Howdy,

Well I have the same motor and I think you may encounter a probably in
trying to stop it at specific steps. The motor controller I use changes
the speed and allows
me to alter the speed range but no matter what speed it is running at
the motor will
coast for a short period of time until it reaches a lower speed. I think
if you want it
to stop at several specific points you may have to use some kind of
electric clutch.

Somehow you have to have the lift disengage from the motor drive to
overcome the

coasting effect of the DC motor.

Is this any help?

dirwi@execulink.com

wanton wrote:

Hi - I am the proud new owner of a 90V Leeson DC 1/4hp motor and KB
electronics control for fun and hobby. I'm really green about this
stuff and I need some info for safety reasons.

The Project: I want to use the motor to make a lift that will go up and
down and stop at any point in between.

The controller manual says I can perform rapid switching on the AC
inputs without damaging anything. Although, It says I cannot perform
this with the DC outputs - else I can expect catastrophic results -
whatever those would be. OK, then without having to purchase a
different controller how do I make this controller work? I need the
motor to go CW and CCW using hopefully a rocker switch of some sort.
Sounds like I might have to have 2 switches, one for the AC on/off and
one to toggle the DC polarity when the AC is off. Sure would be nice
to only use one rocker switch though.

Regarding safety, do I need to mount the switches in a special box or
have specially rated switches, etc.? I don't want to get bit.

Any help is appreciated

It looks like what you have is what is called a non-regenerative, two
quadrant controller, probably using armature voltage feedback. You'll not
get the kind of close control you need out of one of those, they're for
controlling conveyor belts, and things that need to run at constant speed
in one direction.

What you need is a four-quadrant, regenerative controller, which will
actually apply reverse torque for braking. you'll also get reversability
with one of those, without switching. You really nead proper speed
feedback (tachogenerator) to get best performance, though it can be done
without.

With the controller you've got, you're stuck with coast stops, the more
inertia you have, the worse it gets.

You *could* try this (maybe):

In sequence:

Shut off the AC supply

Using a changeover contactor, disconnect the controller from the motor,
then slug a damn' great power resistor of a few ohms across the motor
armature terminals. The motor is now a generator, and its sored energy
(flywheel effect), is being dissipated in the resistor (It'll get hot).
The motor will slow down at a rate determined by the value of the resistor, the
fewer ohms, the faster it slows down, but don't exceed the maximum rated
armature current.

When you've reached the state you want (lower speed or stop), reverse the
above steps.

I didn't tell you that! If you kill yourself or burn the building down,
it's YOUR fault!

Anyway, the switchgear will cost more than a proper controller.

Bring back Ward-Leonard sets, that's what I say

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

DarkMatter · Sep 29, 2004

On Mon, 14 Jul 2003 14:06:24 GMT, "Christopher Klassen"
<klascs@telusplanet.net> Gave us:

Good for you. Take a hike, you fuckhead.

Jim Thompson · Sep 29, 2004

On Tue, 15 Jul 2003 19:22:39 GMT, harp999@excite.com (M. Jakeman)
wrote:

Those plug-in bug repellers - anyone reading this tried them?
I gather they create some sort of force field generated by the house's
wiring that interferes with bugs' nervous system.
How well do they work? In particular, do they keep spiders out of the
house?

Thanks

Jake

480)460-2350 | |
| Jim-T@analog_innovations.com Fax

M. Jakeman · Sep 29, 2004

On Tue, 15 Jul 2003 12:52:02 -0700, Jim Thompson
<Jim-T@analog_innovations.com> wrote:

They block everything *but* spiders. You'll just have to contend with
them walking on your face while you sleep ;-)

Thanks a bunch, friend..

M. Jakeman · Sep 29, 2004

On Tue, 15 Jul 2003 19:28:31 GMT, "Sir Charles W. Shults III"
<aichipREM@OVEcfl.THISrr.com> wrote:

They do nothing.

That's sad! Thanks for the reply, anyway..

Jake

Jim Thompson · Sep 29, 2004

On Tue, 15 Jul 2003 21:00:40 GMT, harp999@excite.com (M. Jakeman)
wrote:

On Tue, 15 Jul 2003 12:52:02 -0700, Jim Thompson
Jim-T@analog_innovations.com> wrote:

They block everything *but* spiders. You'll just have to contend with
them walking on your face while you sleep ;-)

Thanks a bunch, friend..

480)460-2350 | |
| Jim-T@analog_innovations.com Fax

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