magnetic field

[Michael A. Terrell]

scanner80 wrote:

Wow, you are something of a butthead aren't you?
I don't cal the equipment used on patients. I cal the test equipment . I
have been to many oem training classes and (here is the key thing ) I follow
a cal procedure.
Duh! If you know anything about calibration ,you would know you need a
calibration procedure. You seem like you did not know that. I forgive you.
I do know about the equipment used in hospitals and the biomeds who use
them. While the majority of them are good. I have seen things that would
scare the h*ll out of you.
My advise ? STAY HEALTHY!
Once again, for all you good and nice people that offered advise in good
faith , THANK YOU!
Jeff

Anyone working to calibrate test equipment needs an excellent
background in electronics. You haven't even mentioned the proper name
for a calibration lab, so I won't, either.

You need to understand the circuits you work on to know if the
equipment is in need of repair instead of just tweaking a few pots and
changing a few stored values in the unit's memory. Also, you need to
see who you are calling names around here. You are cross posting into
five newsgroups, including a design newsgroup with people who design the
equipment you are playing with.

I have worked around a small cal lab, but my main job was to to test,
align and calibrate boards and modules used in $80,000 receivers. I
wrote a number the test procedures for that product, designed and built
the test fixtures, wrote software for automated fixtures and suffered
through the ISO 9001 certification process.

You sound like the know it all techs who couldn't follow a simple
test procedure to verify a board was good before trying to calibrate
it. I admit this equipment wasn't all used for medical settings but
several medical schools did use our equipment as well as NASA, NOAA and
other government agencies.

John Fields doesn't need me to defend him but he designs
instrumentation, so he is in a lot better position than you to decide
who is right.

--
Link to my "Computers for disabled Veterans" project website deleted
after threats were telephoned to my church.

Michael A. Terrell
Central Florida

 

[John Fields]

On Sat, 6 Aug 2005 20:34:19 -0500, "scanner80"
<scanner80@charter.net> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:tfjaf1dm0mp1p68r05rcu00sp1od421us2@4ax.com...

---
What details???

I don't know how to say this without being insulting, but if I was
in a hospital and being monitored by instruments which you were
supposed to be responsible for, I'd be in fear for my life. How has
it come to pass that you, who has less than a rudimentary knowledge
of even basic electronic circuitry, can be relied upon to perform
calibration on equipment which is critical to the maintenance of
human life?

Wow, you are something of a butthead aren't you?
I don't cal the equipment used on patients. I cal the test equipment . I
have been to many oem training classes and (here is the key thing ) I follow
a cal procedure.
Duh! If you know anything about calibration ,you would know you need a
calibration procedure. You seem like you did not know that. I forgive you.
I do know about the equipment used in hospitals and the biomeds who use
them. While the majority of them are good. I have seen things that would
scare the h*ll out of you.
My advise ? STAY HEALTHY!
Once again, for all you good and nice people that offered advise in good
faith , THANK YOU!

---
Well, if being a butthead means worrying about how a person supposed
to be doing calibrations can't work out how to measure the voltage
excursion and / or the time between two points accurately and that
measurement will affect the outcome of a test made on my body, then
I'll gladly be a butthead. Also, I asked you a post or so ago for
some more detailed information regarding the "resistor", and have
received none. If you post the details and explain a little more
thoroughly what you'd like the instrument to do, i'll be able to
desigh a nice system which will be able to do exactly what you want.

--
John Fields
Professional Circuit Designer

 

[legg]

On Sat, 6 Aug 2005 15:07:56 -0500, "scanner80" <scanner80@charter.net>
wrote:

snip...
...I feel like I'm not qualified to change a 9V battery.
I work in a calibration lab calibrating Medical and test equipment. I also
do a lot of the research. I get ideas
of new ways to do things and try to work on them when time allows or at
home.
I'm not an engineer (as you could probably tell) I only have an Associates
Degree. But I do the best I can and I do alot of research on my own.

Once again THANK YOU ALL VERY MUCH!! . And thank for your time.
I will use your info and work out the details.

Jeff

Considering the costs involved in calibration servicing, it's always

bothered me how many times simple metering is returned with a new
calibration sticker, when the battery(s) were nearly dead and
protective fuses were still open.

Charging for replacements, where required to calibrate, would not have
significantly inceased the bill. No great knowledge of electronics
would have been required to read the equipment manual and perform
these basic functions.

RL

 

[AJH]

alan.webb@DogForAWalkblueyonder.co.uk wrote:

On 27 Jul 2005 04:27:22 -0700, "AJH" <ajhbox-3@yahoo.co.uk> wrote:


OK, solved it. I bought the product you suggested, but the Zire 72
version, here:
http://www.proporta.co.uk/F02/PPF02P05.php?t_id=635&t_mode=des
It does indeed come with a little adaptor (really for the 9v PP3
keyring charger) that takes a Nokia phone charger output plug and
converts to the tiny Zire plug. This works fine, the Zire charges up
Ok. (as long as I use the newer, lightweight Nokia chargers, my old,
fat, square one does not charge the Zire despite claiming it has the
same voltage and similar current output).

In the set also is a USB charger and Car lighter socket to USB, so I
have many charging options now!

However all I really needed was the little adaptor I have described,
and I'd love some more, as I have Nokia chargers all over the place.

Still, as long as I don't lose it I'll be fine.
Thanks for your help.
Alan
Glad you got it sorted. If you ever find somewhere to get just the
adapter let me know as the one for the Tosh e750 also fits my mp3-cd
player and a couple of other gadgets I have.


Alan
Take DogForAWalk before replying by e-mail

"Kleeneze" - the doorstep household goods and now gadgets catalogue
people have sold my wife a USB phone charger, which has as its "output
end" a Nokia-size female connector! It comes with a set of "tips"
including the Nokia.
Still looking for a handful of Zire 72 (0.75mm?) tips.
Alan

 

On 9 Aug 2005 02:32:29 -0700, "AJH" <ajhbox-3@yahoo.co.uk> wrote:

Alan
Glad you got it sorted. If you ever find somewhere to get just the
adapter let me know as the one for the Tosh e750 also fits my mp3-cd
player and a couple of other gadgets I have.


Alan
Take DogForAWalk before replying by e-mail

"Kleeneze" - the doorstep household goods and now gadgets catalogue
people have sold my wife a USB phone charger, which has as its "output
end" a Nokia-size female connector! It comes with a set of "tips"
including the Nokia.
Still looking for a handful of Zire 72 (0.75mm?) tips.
Alan
Sounds like it has the same sort of adapters as the 'emergency

charger' I got from the poundshop - male nokia to male. Still looking
for more of the adapters like the one with the PP3 keyring charger.


Alan
Take DogForAWalk before replying by e-mail

 

[Mike Berger]

You can order the batteries with either size terminal.
There's nothing more or less "standard" about them, and
it's not clear that APC uses a "less popular" size
connector than anybody else.

kony wrote:

Personally I'd buy the more standard battery and swap the
connectors on the APC's battery leads (with appropriate
aftermarket ones).

 

[Fred Abse]

On Mon, 08 Aug 2005 10:21:51 +0000, legg wrote:

Considering the costs involved in calibration servicing, it's always
bothered me how many times simple metering is returned with a new
calibration sticker, when the battery(s) were nearly dead and
protective fuses were still open.

I think we've all been in the situation where equipment sent to a
calibration lab comes back *worse* than when it went.

You can hide a lot of poor workmanship behind cal seals.

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)

 

[J.Luminous]

Probably something amatuer robot builders could use.

 

[b9_2mr]

Personally, if I had noticed that these posts were disappearing from
various forums, my first impression would be that the mods of those
forums felt that the material was either inappropriate, or spam (yes,
the format does strongly resemble forum spam).

 

[awright]

Both the bar magnet and the field around a wire COULD be cancelled if
they were infinitely thin (an impossibility). Neither can be
perfectly cancelled in real life because they are of finite size.
Perfect cancellation could only be achieved by exact superposition of
all elements of the wire or magnet with an element of the opposite
polarity/current direction at the same point in space. Since you can
never achieve such exact superposition due to the physical size of the
wire/magnet, you can never achieve perfect cancellation - only
approximate cancellation, for example, by placing two small wires
very close together. Twisting two wires helps by averaging the
imperfectly cancelled fields from the two wires, but this is also
just an improved, imperfect cancellation.

After all, the absence of a magnetic field around a non-magnetized
piece of iron is due to the micro-scale mutual cancellation of all
the randomly oriented tiny magnetic domains of the iron. They cancel
"perfectly" on a macro scale because the domains are so small and we
are normally sensing the average field of all those randomly oriented
domains. But if you could probe with a micro probe, you would be able
to sense the magnetic field around each minute magnetic domain and you
would see that, at that scale, the cancellation is not perfect due to
the non-infinitesimal size of the domains.

Does this help, or just add to the confusion?

awright

 

[awright]

Pardon my comment, but why on earth would you want to make a
specialty, rare-earth magnet yourself when there are very well
qualified companies with vast experience at the process? Sounds kind
of like wanting information on how to make an integrated circuit in
your basement.

I am an inveterate Do-It-Yourselfer, but there are limits. You are
unlikely to save money by trying to make magnets at home. It
requires knowledge of and sources for the specific, exotic materials
and the appropriate mix/alloy for the properties you want, sintering
furnaces, dies and presses, precise temperature control, ability to
apply the correct magnetic field while the material is above the
Curie temperature, specialty coatings and ability to bake them on
(if you use powder coatings) without depolarizing your magnet, etc.,
etc.

"Physics Today" 2003 Buyers' Guide lists a dozen or two magnet
manufacturers. Go to www.physicstoday.org/guide, select (M)agnets,
permanent (or the category you want), and you get the list.

"magnets, permanent" brings up:

Angstrom Sciences Inc.
Dexter Magnetic Technologies Inc.
Global Equipment-Magnetics Division
Integrated Magnetics
MagnaPlan Corp.
Magnetic Component Engineering Inc.
Magstar Technologies
National Imports LLC
TeachSpin, Inc.

One or more of them may even have what you need as a standard item in
their catalog, or at least have dies to make what you need..

Good luck.

awright

 

[CL (dnoyeB) Gilbert]

Vidar Lřkken wrote:

CL (dnoyeB) Gilbert <Fake@ThisOneIsFake.com> wrote this in
ZuSdnWrgcLYdL5reRVn-og@comcast.com>:

If the warning beeper is what you dont like why not open the unit up
and disable the little speaker that makes all the noise, suggested
ways are crush with pliars, remove from board, stuff hole with cotton
and glue or plug hole with screw. Would leave you with the little
light that flashes when in battery mode.



to be fair, 10 years ago when i had a low end apc, even that one you
could disable the beeping on.



This is not true on low-end APC today. Please avoid cheap APC. Expensive
APC is really nice, but then again, it is expensive.

Then its even more consistent with what I have heard. APC is removing
features to create line differentiation as opposed to innovating and
adding new features. Shame...

--
Respectfully,


CL Gilbert

--
Respectfully,


CL Gilbert

 

[Vidar Lřkken]

CL (dnoyeB) Gilbert <Fake@ThisOneIsFake.com> wrote this in
<nu6dnaWsG-h0CJXeRVn-gQ@comcast.com>:

Vidar Lřkken wrote:
CL (dnoyeB) Gilbert <Fake@ThisOneIsFake.com> wrote this in
ZuSdnWrgcLYdL5reRVn-og@comcast.com>:

If the warning beeper is what you dont like why not open the unit up
and disable the little speaker that makes all the noise, suggested
ways are crush with pliars, remove from board, stuff hole with
cotton and glue or plug hole with screw. Would leave you with the
little light that flashes when in battery mode.



to be fair, 10 years ago when i had a low end apc, even that one you
could disable the beeping on.



This is not true on low-end APC today. Please avoid cheap APC.
Expensive APC is really nice, but then again, it is expensive.


Then its even more consistent with what I have heard. APC is removing
features to create line differentiation as opposed to innovating and
adding new features. Shame...

Yep, I guess that might be the case. High end (with snmp and all that
kind of stuff) performs really nice, and has huge performance. On the
other side, things like BackUPS 350/500/750 is a POS. The 500 has ugly
sine wave and long switch-time.
So please, don't buy apc unless you intend to spend 1000$ on a UPS. Then
it is the best there is!

--
MVH,
Vidar

www.bitsex.net

 

[Michael Gray]

On Mon, 27 Jun 2005 03:48:37 -0700, Ron Thompson
<rthompso6161@yahoo.com> wrote:

Does anyone know of a method of either locating or finding information
about transistors that were manufactured in 1972? I am specifically
interested in locating or finding info on two transistors; their codes
are: 2N5809 and 2N9614. I can't seem to find any supplier that has them
so I am presuming they are no longer manufactured. Thanks for whatever
help you can give me.

Ron Thompson

The 2N9614 is mentioned in a patent as a PNP Transistor.

United States Patent 5524894
Head movement sensor for golf practice
Issued on June 11, 1996

http://www.patentstorm.us/patents/5524894.html

 

[Bret Ludwig]

The Web is rapidly replacing trade magazines-the free-to-the-reader,
bingo card publications popular for decades which are sent free to
readers claiming to be occupied professionally in the trade they cater
to.

In both cases, advertisers pay per reader-per click in the case of
websites and per mailed magazine (as audited by independent services
providing only somewhat fungible numbers) in the case of magazines.

Decades ago, someone-probably a disillusioned desert rat hippie on the
lam from a dreary East Coast industrial existence with major Oedipal
issues-promoted the idea that if you had some vague interest in the
subject these publications catered to, you should put down a bunch of
shit on the little bingo card telling the publisher what he wants to
hear and he will put you on the list to get the magazine, absolutely
free of charge.

Now, there is a fraud being pulled here, but it is not against who you
think.

Are you defrauding the obvious victim, the publisher? In theory,
maybe, but in practice no. He gets paid on an ad card rate that gets
higher the more he sends out, and so he will put anyone on that list if
they fill out the card the way he transparently tells you to fill it
out. He can show it to his auditors saying he has the card in hand and
that's why Joe Doakes is on the list, even if Joe Doakes is a curious
13-year-old, an old loner just wanting free bird cage liner, or a
liberal shit disturber looking for ways to pass laws or organize
protests to fuck with the companies in the trade. Indeed, any trade
magazine mails out a fair number of subscriptions it well knows are
going in the landfill unread. Since audits only expect a percentage of
the percentage they "randomly" select to pass "audit", any publisher is
going to pack the names by having office staff scribble on hundreds of
bingo cards, names of nursing home residents, random industry
sourcebook listings, and the occasional total fictional name and
address.

The defraudee here is the advertiser. He is paying for ten thousand
electronic product designers to see his ad, not a thousand electronic
designers, a thousand college students, five thousand hobbyists and
three thousand Alzheimer's patients. But what's his alternative?

Carry this out to the successor of the trade magazine, the sponsored
Web site. If you are paying per click, ask yourself: are the clicks
from serious searchers for your product, or every bozo who comes across
a Usenet link in every newsgroup catering to pseudoscience buffs,
half-ass dreamer-inventors and assorted douchebags the Web site's
author is ass-blowing all over?

It's your money. But if I were paying-per-click, I'd have a
no-shitting-over-Usenet clause in the contract.Or you will pay for
every moron who listens to Fart Smell to see your site on cross
compilers for 32-bit embedded RISC micros.

 

[John Smith]

AS FOR YOU, SAY SORRY TO YOUR MOTHER BECAUSE YOU JUST PROVED THAT SHE
DEFINITELY FAILED TO RAISE YOU WELL...

Unlike your mother, who failed to give birth to someone with eight fingers
and two thumbs. Try releasing the CAPS lock, and STOP SHOUTING AT US.

Prick.

 

[SP]

Hi,
I would appreciate if you could provide some further info.
Is there any electronics FAQ that can be used by designers? Please pint
to me.
Thanks
PS

 

[default]

On 19 Oct 2005 05:55:17 -0700, "SP" <prem.sivasamy@gmail.com> wrote:

Hi,
I would appreciate if you could provide some further info.
Is there any electronics FAQ that can be used by designers? Please pint
to me.
Thanks
PS

An FAQ that spans the entire breadth electronic design?

That would be a lengthy tome indeed . . .

You may want to narrow the span of your search a bit.
--

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

 

[Tomi Holger Engdahl]

"SP" <prem.sivasamy@gmail.com> writes:

Hi,
I would appreciate if you could provide some further info.
Is there any electronics FAQ that can be used by designers? Please pint
to me.
Thanks
PS

Try www.epanorama.net

Lots of electronics information, many webpages with basic
inctroduction texts for many topics and links to more information.


--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/

 

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