HDTenEightyP/NetNews huggingface dataset:
From: massoud@chemteca.sdsu.edu (Massoud Ajami)
Newsgroups: sci.electronics
Subject: Re: Nuclear Magnetic Resonance (NMR/MRI)
Date: Thu, 17 Dec 1992 17:33:51 GMT
Organization: San Diego State University
NNTP-Posting-Host: 130.191.227.22

In article <BzDI7y.53I@cantua.canterbury.ac.nz> geoffrey@cosc.canterbury.ac.nz (Geoff Thomas) writes:
>Subject: Nuclear Magnetic Resonance (NMR/MRI)
>From: geoffrey@cosc.canterbury.ac.nz (Geoff Thomas)
>Date: Wed, 16 Dec 1992 22:23:57 GMT
>
>I am wondering whether an NMR machine could be run 'inside-out'. As
>far as I understand them, NMR imagers consist of a toroidal magnet
>system, through which the subject is placed. Would it be possible to
>use a bar magnet type of configuration so that the subject didn't
>need to be placed within the physical magnet structure?
>
>i.e.
>this:				instead of this:
>...........			    MMMMMMM
>...........			  MMMMMMMMMMM
>...........			MMMMMMMMMMMMMMM
>MMMMMM.....			MMMM...SS..MMMM
>MMMMMM.....			MMMM.SSSS..MMMM
>...........			MMMM..SS...MMMM
>.SS....S...			MMMM....S..MMMM
>SSSS...SS..			MMMMMMMMMMMMMMM
>..SSSSSS...			  MMMMMMMMMMM
>...........			    MMMMMMM
>
>where:
>M = magnet structure
>. = magnetic field
>S = subject
>
>
>Can it be done? What range would the system typically be capable
>of measuring? How big would it be? How much power would be required?
>
>Any help much appreciated. Thanks in advance,
>Geoff Thomas

To do NMR, you need uniform field. Single bar magnet can not produce that,
then you need to couple it with another bar magnet in the opposite side, and 
to contain the field, the magnets have to be coupled together, which you 
end up to have a toroid, and subject between the poles. To do imagine, 
you need to add gradiant field to it.
By the way, the toroid you are thinking, has zero field outside the core.   

--
Peace and Prosperity!
  ---==< 110 >==---
Xref: sparky sci.electronics:21241 sci.energy:6299 rec.autos.tech:16978
From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Date: 20 Dec 1992 23:35:07 GMT
Organization: HST Wide Field/Planetary Camera
Distribution: world
Reply-To: carl@SOL1.GPS.CALTECH.EDU
NNTP-Posting-Host: sol1.gps.caltech.edu

In article <72053@cup.portal.com>, lordSnooty@cup.portal.com (Andrew - Palfreyman) writes:
>Re. the exploding flywheel: I was mulling on flash-filling the
>cavity with thick-setting foam, but I imagine that the response
>time is way too long compared with the split of the wheel.
>Comments?

Even if the response time weren't too long, this "foam" would merely be yet
another thing for the flywheel fragments to vaporize, and would almost
certainly only exacerbate the problem.  Why do so many people have so little
grasp of the amount of energy we're talking about, here?
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
Newsgroups: sci.electronics
From: philb@techbook.com (Phil Biehl)
Subject: Capacitor book
Organization: TECHbooks of Beaverton Oregon - Public Access Unix
Date: Tue, 15 Dec 1992 22:23:36 GMT

I seem to recall seeing an ad for a book on capacitors. I don't recall
where I saw it or any other details. If you know of such a book could
you please pass on said info? Thanks much.

Forgetfully yours,

Phil Biehl
Home Row, Inc.


philb@techbook.COM  Public Access User --- Not affiliated with TECHbooks
Public Access UNIX and Internet at (503) 220-0636 (1200/2400, N81) 
-- 
philb@techbook.COM  Public Access User --- Not affiliated with TECHbooks
Public Access UNIX and Internet at (503) 220-0636 (1200/2400, N81) 
Newsgroups: sci.electronics,rec.audio,rec.music.makers.guitar,alt.guitar
From: till@acid-rain.lucid.com (Don Tillman)
Subject: Amp question
Reply-To: till@lucid.com
Organization: Lucid, Inc.
Date: 17 Dec 92 11:00:35

   From: dcovell@hfglobe.intel.com (David Covell)
   Organization: Intel Corporation
   Date: Wed, 16 Dec 1992 19:57:03 GMT

   Older Fender amps use a black material as a substrate for the point-to-
   point wired circuitry. What is this stuff, what's its proper name, and
   where can I get some (or an acceptable substitute)?  
   The material is black, semi-flexible, about 3/32" thick, and I assume it
   has high dielectric value. Probably very tolerant of high temperatures also.
   I don't care if it's not identical to the original Fender material as long
   as it works in similar applications.

It's called a terminal board or a turret strip.  The ones used on the old
Fender amps were wax impregnated cardboard of some sort, but nowadays
("nowadays" in the geologic sense, ie., over the last two or three decades)
nice robust epoxy versions with far better electrical and thermal
characteristics are available.  (At least that's what I used back in '75.)

  -- Don
From: cmh@eng.cam.ac.uk (C.M. Hicks)
Newsgroups: sci.electronics
Subject: Re: DSP info
Date: 17 Dec 92 13:09:00 GMT
Organization: cam.eng

fzteller@betty.ucdavis.edu writes:


>Does anyone know of a site on the net where I can get info on the following 
>fields?
>  
>  Digital Signal Processing
>  The operation of the "Digital Out" jack on some CD players
>  Digital Filters
>  Basic Digital audio data

Try comp.dsp and rec.audio.pro for starters. They both have an FAQ I think.

Christopher 


-- 
 ==============================================================================
 Christopher Hicks    |    If it doesn't fit...
 cmh@uk.ac.cam.eng    |                        ...you need a bigger hammer.
 ==============================================================================
--
 ==============================================================================
 Christopher Hicks    |    If it doesn't fit...
 cmh@uk.ac.cam.eng    |                        ...you need a bigger hammer.
 ==============================================================================
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
From: gregor@kafka.saic.com (gregg hanna)
Subject: Re: Flywheel batteries as EV power source
Reply-To: gregor@kafka.saic.com
Organization: Science Applications International Corporation
Date: Fri, 18 Dec 1992 03:23:10 GMT


I've wondered about this in other contexts, but I think it applies
to the flywheel discussion quite well...

Since Halon works by interferring with the burning process, what
would happen if a mass of gassified flywheel housing breached a Halon
tank, thus releasing Halon, on the way to mixing with the air?

At least some energy would be absorbed heating up the Halon as it
expands from the tank, and then the mixture would hit air.
What would this look like?  I know the heat has to go somewhere,
but since the Halon interferes with combustion would it mitigate
the damage?

                                         gregg hanna
                                         gregor@kafka.saic.com
Organization: University of Illinois at Chicago
Date: Thursday, 17 Dec 1992 01:44:10 CST
From: Jay Lorenzana <U40348@uicvm.uic.edu>
Newsgroups: sci.electronics
Subject: Going from the EVM to the 'Real Thing'

Dear netters,

I am going to build my first real embedded controller using
the 6811 and I have a couple questions in jumping from
the EVM to the 'real thing.'

1.  Do I have to ORG the variables defined using
    FCB, FDB, RMB,... such that they reside in RAM?

    I have been using the EVM and all programs and
    stuff reside in seudo-ram at $E000 and am
    suspicous of the user variables.

2.  How do I go about programming an interrupt vector?

    The interrupt vecors reside in ROM in the 'real thing!'
    The EVM has seudo-vectors located in user ram
    but what about the real thing?

3.  What other complications may I expect from going
    from the EVM to the 'real thing' in single
    chip mode?


4.  Another off the wall question is:  What is
    the max current a 30AWG wire-wrap wire can handle?


Thanks for any help you can offer..

-Jay
         Univeristy of Illinois
               at Chicago

                                   Internet: U40348@uicvm.uic.edu
                                   Bitnet  : U40348@uicvm.bitnet
From: miller@hmsp04.wg3.waii.com (Griff Miller X7114)
Newsgroups: sci.electronics
Subject: Re: D O E S   A M E R I C A   S A Y   Y E S   T O   J A P A N ?
Date: 11 Dec 92 22:01:38 GMT
Organization: Western Geo. - Div of Western Atlas Intn'l Inc., Houston, TX

In article <31030@nntp_server.ems.cdc.com> tbruseha@hollywood.ems.cdc.com (Tom Brusehaver) writes:

>Think about what you do.  As a parent your influence is incredible.
>If you sit on the couch with the remote in one hand and a beer in the
>other, what will the kid do?

Tom, wiser words have seldom been spoken. I can only add that we need
to teach responsible behavior through example, also. There is a growing
tendency in this country for people to look for a way out of a difficult
situation rather than shouldering their load.

Take honesty. Suppose your child skips school. Would you write a sick note
so that your child's record won't be marred with an unexcused absence?
--
Griff Miller > miller@monarch.wg3.waii.com < use this for email.

          *** My opinions are mine, not Western's. ***

   "The fear of the Lord is the beginning of knowledge, but 
    fools despise wisdom and discipline."   - Proverbs 1:7 
Newsgroups: sci.electronics,rec.audio,alt.guitar,rec.music.makers.guitar
From: npstewar@eos.ncsu.edu (NATHAN PHILLIP STEWART)
Subject: Re: Tube amp transformers
Originator: npstewar@c00722-239rd.eos.ncsu.edu
Keywords: tubes transformers
Reply-To: npstewar@eos.ncsu.edu (NATHAN PHILLIP STEWART)
Organization: North Carolina State University, Project Eos
Date: Mon, 14 Dec 1992 17:46:59 GMT


I pulled out the schematics section of my Groove Tubes book, and was looking
through some classics the other night in light of our discussion of maximum
tube voltages.  I found some interesting things, which generated some questions.

1) What exactly is the relation between plate voltage and the level where output
   distortion begins. As far as I understand it now, the higher the plate 
   voltage, the higher output level before distortion sets in. Is this the
   relationship? Is it more complex than this? (of course it is)

2) With the Deluxes, plate volage ran from 350V to 410V from early years to
   later years for 6V6's.  With various other Fenders using 6L6's, plate voltage
   ran up to 470V on later years, but some early models were under 410V.
   Does this mean that as long as my amp with 6L6's has a plate voltage of 410V
   or less that I could use 6L6's? If it could work, would it be effectively
   lower my power output but mean that my power section might not be able to
   distort?

3) About measuring plate voltage, it occured to me that if the impedance of 
   my voltmeter is not high enough I could fry my voltmeter and quite possibly
   more (me for instance.)  Is this a real concern, or do Multimeters generally
   have a high enough impedance that I don't need to worry.

4) If I want to leave my 6L6's, but drop their plate voltage (This depends on
   the answer to the first question), without changing my transformer, can this
   be done.  (Since my carvin uses some FET EQ circuits and reverb buffering,
   I can't just sub a lower power transformer.)

npstewar@eos.ncsu.edu
Nathan Stewart
Newsgroups: sci.electronics
From: mazzucch@ghost.dsi.unimi.it (massimo mazzucchi)
Subject: DAS 9200: info
Organization: Computer Science Dep. - Milan University
Date: Mon, 14 Dec 1992 13:03:01 GMT


Hi 

i am MAx Form Milan Italy

I have a program DAS 9200 of Techtronic this is a emulaton of

processor but i have the problems about it.

If you know it, please write me.


Bye Max


--------------------------------------------------------------------------------
!  Massimo Mazzucchi                         address    e-mail                !
!  University of State                       mazzucch@ghost.dsi.unimi.it      !
!  Departement of Computer Science            149.132.2.1                     ! 
!  Via Comelico, 41 -  20133 MILAN ITALY                                      !
 -------------------------------------------------------------------------------
From: bg@ccwf.cc.utexas.edu (Brent Goodrick)
Newsgroups: sci.electronics
Subject: Netlist Node Labeling within MicroSim's Schematic Program
Keywords: 8051
Date: 15 Dec 92 21:02:25 GMT
Organization: The University of Texas at Austin, Austin TX

I have the shareware student version of MicroSim's Schematic Simulator
(the one that runs under Windows), but I do not have access to any
reference manuals.  Here's my question:  How do I tell the program
to display the names of the nodes that are passed to PSpice via the
netlist file?  For example:  I have setup a simple circuit with a 3V
independent voltage source in series with a 1ohm resistor and a 2ohm
resistor.  This is the netlist generated by the Schematic Simulator:

* Schematics Netlist *

v_V1     $N_0002 0 dc 3v  
R_r1     $N_0002 $N_0004 1ohm 
R_r2     $N_0004 0 2ohm

If possible, I want the program to display the nodes "$N_0002" and
"$N_0004" in the appropriate places on screen, kinda like this:


                          node $N_0002
             +--------------------------------+
             |                                |
             |+                               |
      V1voltagesource                     1ohmresistor
             |-                               |
             |                                | node $N_0004
             |                                |
             |                            2ohmresistor
             |                                |
             |                                |
             +---------------+----------------+
                             |
                            grnd

Otherwise, I spend a lot of time trying to figure out what the program
has assigned as the plus node of a resistor, which really is misnomer
anyway.

Thanks in advance
Brent Goodrick - Electrical Engineering - University of Texas
bg@ccwf.cc.utexas.edu

Newsgroups: sci.electronics
From: nasiom@hall105.its.rpi.edu (Milton Peter Nasiopoulos)
Subject: Re: Blue LED manufacturer
Reply-To: nasiom@rpi.edu
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Fri, 18 Dec 1992 20:02:32 GMT

In article <1992Dec18.174418.26190@bernina.ethz.ch>, peny@ppc.lpc.ethz.ch (Peter Nyffeler ,x4399) writes:
|> Wasen't there samoone looking for blue LED's?
|> 
|> I saw an advertisment of STANLEY ELECTRONIC Japan that they produces blue LED.
|> This firm is well representated in Europe and I think in USA too.
|> 
|> --------------------------------------------------------------------------------
|> 						  __________
|> Peter Nyffeler					 / ___  ___ \
|> ETH-Zuerich, Physical-Chemistry-Lab.		/     \/     \ 
|> Switzerland					|  ___  ___  | Soaring
|> e-mail:peny@ppc.lpc.ethz.ch			|     \/     | Club
|> fax: ..41 1 252 34 02				|  ___  ___  | Zuerich 
|> tel: ..41 1 256 43 99				\     \/     /  
|> 						 \__________/ 
|> 					     + Control-line modell enthusiast
|> --------------------------------------------------------------------------------
|>  
|> 

 I know a place in the US. that sells 'em for $1.75 each.  I forget the 
place but if you e-mail me to remind me to post it I'll post it next week.


milt.
Newsgroups: sci.electronics
From: sehari@iastate.edu (Babak Sehari)
Subject: Re: Transmission line question
Originator: sehari@class1.iastate.edu
Organization: Iowa State University of Science and Technology, Ames, Iowa.
Date: Wed, 16 Dec 1992 11:10:35 GMT

In <1992Dec15.202004.15878@ucsu.Colorado.EDU> barr@tramp.Colorado.EDU (BARR DOUG) writes:

>Some specs I have call for ethernet coax to be grounded in one location
>and one location only! I am wondering why this is. Antenna effects,
>current loops or something else. Does anyone know why this is the case?

If he distance is large enough, and the two end points are at two different
potentials, you might blow up the whole computer.  Remember, the two end
points are not connected with %100 conductive material.  The two end point
might be connected by earth or other much less conductive materials.  When
you connect them with a conductor, such as the shield, this conductor
wants to create zero potential between these two ends. This requires very 
large current passes through the wire, which might damage the computer.
Also, there might be some voltage from change of magnetic flux of the big 
loop.

                          With highest regards,
                               Babak   Sehari.
-- 
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
From: eric0139@student.tc.umn.edu (Grant Erickson)
Subject: Re: Flywheel batteries as EV power source
Followup-To: sci.electronics,sci.energy,rec.autos.tech
Organization: University of Minnesota
Date: Fri, 18 Dec 1992 01:49:25 GMT

I am not certain as to the relevance of this, but this topic seems to be
pretty hot with the Physics department at the U of M. The professors have
brought out several newly built flywheel demonstrations, etc. And on the
final, we were given the following question:

Estimate the practicality of using a flywheel to store energy to operate a
car. Suppose a car needs a road power of 30 HP. Suppose that the flywheel
had a mass of 100 Kg, and in fitting in a small part of the trunk. Take it
to be a cylinder of radius 30 cm. How fast must the flywheel rotate to have
enough energy to operate the car for one hour? What would be the maximum
centripetal acceleration of a point on the rim?

I realize this is "easy" freshman physics to most of you, but the theory is
certainly of interest.

.___________________________________________________________________________.
| Grant Erickson                                                           
|
|   eric0139@student.tc.umn.edu     University of Minnesota / Twin Cities  
|
|   granteri@pnet51.orb.mn.org      People's Network 51 / Minneapolis      
|
|---------------------------------------------------------------------------|
| Please obeserve the 55 MPH speed limit, the drivers passing you could use
|
| the laugh.                                                               
|
'---------------------------------------------------------------------------'
From: gw214790@LANCE.ColoState.Edu (Galen Watts)
Newsgroups: sci.electronics
Subject: Re: Handling CMOS
Date: 20 Dec 92 18:03:50 GMT
Organization: Colorado Concert Sound

In article <JON_SREE.92Dec19224851@world.std.com> jon_sree@world.std.com (Jon Sreekanth) writes:
>In article <1992Dec14.120707.13760@eng.cam.ac.uk> cmh@eng.cam.ac.uk (C.M. Hicks) writes:
>Galen Watts Wrote:
>   >>The way I install CMOS chips is in the bathroom.  Take the circuit board, all
>   >>the tools you might need and the chips into the b-room and close the door.
>   >>Run the shower on HOT for a few minutes, until the mirror fogs over.  Leave the
>   >>water running (maybe turn it down a little), touch the board and the package the
>   board simultaneously while handling the chip. All this bathroom stuff seems
>   bizarre - do you get contact corrosion because of water trapped in the
>   sockets :-? BTW, conductive foam is much more usable than foil.
>Why not just buy a $50 humidifier from the nearest department store ?
>Working in the bathroom with the water running seems a bit much.
>/ Jon Sreekanth

Why should I buy a $50 humidifier when the bathroom is free?  Why is everybody
so hung up on not doing something in a slightly different way?  If you'll look
at who I work for, you may be able to figure out that I don't always do repairs
in the shop, sometimes my shop is 2000 miles away, and trying to get a room for a humidifier can be a major hassle, so I fog up a dressing room.  If you only
stay in the room long enough to put in the chip, you don't get condensation
enough to corrode contacts.  When you step out of the room, the moisture
evaporates quicly enough to not be a problem.
BTW, conductive foam is not always available, and it eats the pins.  Often, the
cute ladies in the catering room are more than happy to give me a sheet of foil.

Someone asked for an easy and cheap way to plug CMOS chips without the 
possibility of damage, and I responded.  I didn't say it was the only way.

Lighten up, eh?
Galen Watts, KF0YJ
Newsgroups: sci.electronics
From: cep4478@ultb.isc.rit.edu (C.E. Piggott )
Subject: DX2 compatible boards?
Originator: cep4478@ultb
Reply-To: cep4478@ultb.rit.edu ()
Organization: Rochester Institute of Technology
Date: Wed, 16 Dec 1992 18:40:22 GMT


What's the difference between a 486-DX2 compatible board and an ordinary
486 board?  Could you take a 486-33 out of a 486-33 board, plug in a
486-66Dx2, and expect it to work?

Chris
-- 
Christopher E. Piggott, WZ2B                    cep4478@ultb.isc.rit.edu
President                                       wz2b.ampr [44.69.0.1]
Rochester Institute of Technology               wz2b @ WB2PSI.#WNY.NY.USA.NA
Amateur Radio Club K2GXT                        CEP4478@RITVAXA.BITNET
From: kennehra@craft.camp.clarkson.edu (Rich"TheMan"Kennehan)
Subject: Re: "The Glob" Atari 2600 processors ???
Organization: Clarkson University
Date: Thu, 17 Dec 1992 17:55:30 GMT



HI.  Ok..."the glob" is impossible to remove.  Is there some way to
melt the protective covering off without losing the data?  Also, how
would I tell what kind of chip is underneath the glob?

- Rich
  kennehra@logic.camp.clarkson.edu
From: jlegg@neptune.phys.ufl.edu (Jeff Legg)
Newsgroups: sci.electronics
Subject: Re: What are the threshold levels for RS-232?
Date: 17 Dec 92 14:46:11 GMT
Distribution: usa
Organization: University of Florida Physics Department - CMT Group

In article <widow.723866984@camelot> widow@camelot.bradley.edu (Shaun Burnett) writes:
>
>	I know that the RS-232 voltage levels are +9 V for high level
>	and -9 V for a low level.  However, how far can you deviate
>	under +9 V and still have the signal considered a high level?
>	Also, how high can the voltage be increased from -9 V and
>	still have the signal considered a low level signal?
>
>	Thanks.
>

The RS-232C and V.28 specifications state a 0 logic level is greater than 
+3 volts and a 1 logic level is less than -3 volts.  Most modern chips 
surpass this standard and will switch between a 1 at .8 volts and a 0
at 2.4 volts.  Hysteresis is 200mV for the MAX2XX series and the delay
time is 350nS for negative going inputs and 650nS for positive going
inputs.
The specification provides for serial communications at up to 20,000 baud
at 50 feet provided capacitance is less than 2500pF.  (Cable length can 
be greater but distributed load capacitance must remain under 2500pF)

Regards,
Jeff