HDTenEightyP/NetNews huggingface dataset:
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: How do anti-theft systems in Shops work ???
Keywords: security shops theft
Organization: Northeastern Ohio Universities College of Medicine
Date: Wed, 15 Apr 1992 17:59:55 GMT

There are several systems in use.  Some systems use a small
resonant foil print on the back of the price tags.  When you check
out, the clerk uses a probe passed trhough holes in the tag to
touch the foil and burn out the resonant circuit.  The sensors by
the dorr operate as a grid dip meter to detect the non burned out
tags.

Our local library uses magnetic strips slipped into the spine of
the book.  The strip can be magetized and degaussed to control its
resonant freqnecy.

One store I visted used tags that actually had diode chips attached
to the back of the tages.  My presumption is the diode operates as
a mixer when the tag is pulsed generating an image frequency that
is easy to detect.  A postmortem on one of the price tags showed
that this system is similar to the first, but it is the diode chip
that is destroyed rather than the antenna foil pattern.

-- 
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu   (140.220.1.1)
From: bergek@fy.chalmers.se (Martin Bergek)
Newsgroups: sci.electronics
Subject: Do you know this IC? Please!
Keywords: ISD
Date: 10 Apr 92 14:12:58 GMT
Distribution: sci.electronics
Organization: Chalmers University of Technology, G|teborg, Sweden

Netters!
        I have a IC which I cannot find listed in any book and I need
to find out what kind of circuit it is as it (probably) contains data 
which I want to read. It is marked in the following way:

    ! ! ! ! ! ! ! ! ! ! ! ! ! !
   -----------------------------
   !                1016AP     !
    >       ISD     9202       !
   !                A134184F   !
   -----------------------------
    ! ! ! ! ! ! ! ! ! ! ! ! ! !

        If anybody out there in netland has any idea what this is I'd
appreciate it if you'd mail me. It would mean a lot to me. Thanks!

     Ciao,
             Martin Bergek
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
! Chalmers University of Technology ! He that of greatest work is finisher,  !
! Gothenburg, Sweden                ! Oft does them by the weakest minister. !
! e-mail     bergek@fy.chalmers.se  ! Shakespeare; All's well that ends well!
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
-- 

     Ciao,
             Martin Bergek
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Xref: sparky sci.electronics:8667 rec.music.cd:4074 rec.audio:7568
From: gary@ke4zv.uucp (Gary Coffman)
Newsgroups: sci.electronics,rec.music.cd,rec.audio
Subject: Re: requesting CD player advice
Date: 17 Apr 92 15:33:24 GMT
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Gannett Technologies Group

In article <kun1bdINN33c@exodus.Eng.Sun.COM> nemeth@helix.Eng.Sun.COM (Les Nemeth) writes:
>
>What I was refering to was what I suppose would be termed as coloration
>of the sound, not necessarily distortion. Or, does coloration show up as
>some form of distortion? I think not... Something that has a warm sound
>to it, could be considered to sound muddy. Just like something that has
>cold/hard sound could be termed as tinny. In either case, you end up with
>listener fatigue after only a short period of time. But, more so with 
>the tinny effect.

Yes coloration *is* distortion of the waveform, often an intermodulation
product, sometimes referred to as "muddy". The perfect reproducer has zero 
coloration. It doesn't have exaggerated high frequency response, making it 
"shrill or harsh". And it doesn't have poor low frequency response, making 
it "tinny". All these are measurable distortions of the original waveform. 
Any frequency response other than absolutely flat over the audible band
is a distortion.

In any Hi Fi system, the major source of intermodulation distortion,
group phase distortion, and frequency response distortion is the 
loudspeaker. Generally they are no better than 7% total distortion. 
That's why a recording can never duplicate a live performance. Even 
if the recording is perfect, and the medium is perfect (as it is with 
the CD), the loudspeaker is going to dominate the sound. Arguing about
putting smaller tap shoes on angels so more can dance on the head of
a pin is irrelevant when you have an elephant trying to join them.

Gary
From: mcovingt@athena.cs.uga.edu (Michael A. Covington)
Newsgroups: sci.electronics
Subject: Re: Front panel finish
Date: 9 Apr 92 19:26:27 GMT
Organization: University of Georgia, Athens

In article <1992Apr8.174210.2068@cco.caltech.edu> franko@cco.caltech.edu (Frank Joseph Filipanits) writes:
>
>I've had great success with printing a front panel on an acetate (transparency)
>and then using an "art fixative" spray glue to tack it to the panel.
>3M and others make this glue, it comes in aerosols <sp?> for ~$5 ea.
>I did a panel this way over a year ago, and there's no peeling or yellowing.
>
Or print on an Avery full-page translucent plastic laser-printer label,
cut it out, and stick it on.  An overcoat of clear Krylon is optional.

I've had a label of this kind with my name and address on it on my
laptop computer for 2 years and there's no visible wear, even though
it gets rubbed every time I put it in its case (almost daily).
-- 
==========================================================================
Michael A. Covington, Ph.D. |  mcovingt@uga.cc.uga.edu  |  ham radio N4TMI
Artificial Intelligence Programs | U of Georgia | Athens, GA 30602  U.S.A.
==========================================================================
Organization: Penn State University
Date: Monday, 6 Apr 1992 16:04:54 EDT
From: <GNR100@psuvm.psu.edu>
Newsgroups: sci.electronics
Subject: Re: PSpice 5.0a Uploaded to SIMTEL
 <11211@ksr.com>

      I'm an en EET major at Penn State, and although I have ftp access, I
cannot get into Simtel.  Could somebody please e-mail the package to me,or tell
me another way to get it?    Thanks alot.





                                 Gordon Rogers
                                 gnr100@psuvm.psu.edu
From: strong@tc.fluke.COM (Norm Strong)
Newsgroups: sci.electronics
Subject: Re: Hex-FET's and infinite im
Date: 15 Apr 92 19:28:06 GMT
Organization: John Fluke Mfg. Co., Inc., Everett, WA

In article <gate.9uo2iB1w164w@toz.buffalo.ny.us> cyberman@toz.buffalo.ny.us (Cyberman) writes:
}DS>I just got a car audio amplifier from Coustic.  In the manual, it says it
}DS>uses hex-FET's and NOT to turn the amplifier on if there is no load on the
}DS>outputs.
}
}DS>I don't know anything about hex-FET's, but it seems unusual that an infinite
}DS>output impedance would cause damage to a transistor.  However, I'm always
}DS>learning just how much I don't know, so if someone could enlighten me in the
}DS>ways of hex-FET's or why this might cause damage, I'd be grateful.
}
}A hex fet is a high power MOSFET.  They work by having a metal
}oxide capacitor on the gate of it's internal fet.  Hex fets have
}a large surface and have thousand of fets in parallel.  anyhow.
}The reason they say this is it may build up a charge on the
}internal capacitors that exceed it's dielectric strength and
}internal voltage limits.  thus it would SELF destruct.

Really now, can you imagine a company of even minimal responsibility
putting an amplifer on the market that can be instantly destroyed if the
speaker leads open?  What would happen if the speaker was fused and the
fuse blew?  Would you expect the amplifier to go south at the same
time?  

If I designed a circuit of that level of stupidity, I'd want to do it
under an alias--and get out of the country immediately after submitting
my schematic. 

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
From: ah157@cleveland.Freenet.Edu (Rob Henry)
Newsgroups: sci.electronics
Subject: walkie talkies
Date: 17 Apr 92 04:12:44 GMT
Article-I.D.: usenet.1992Apr17.041244.14580
Reply-To: ah157@cleveland.Freenet.Edu (Rob Henry)
Organization: Case Western Reserve University, Cleveland, OH (USA)



If you know anything about walkie talkies please leave me MAIL.
I need to know the operating frequeny,I need 46 or 49 Mhz.
I also need to know how this frequency can possibly be adjusted.
Thanks
Please LEAVE MAIL
Rob
Newsgroups: sci.electronics
From: medin@catbyte.b11.ingr.com (Dave Medin)
Subject: Re: How much protection do I need?
Reply-To: medin@catbyte.b11.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Date: Tue, 14 Apr 1992 22:27:37 GMT

In article <1992Apr13.043121.11482@athena.cs.uga.edu>, mcovingt@athena.cs.uga.edu (Michael A. Covington) writes:
|> I have had no trouble using 7805-type voltage regulator chips as the
|> only thing between the automotive 12V line and the device I wanted to
|> power.  Well, maybe put an RF choke ahead of it too...
|> 
|> By the way, most of the ripple in the 12V line comes from the spark
|> plugs firing.  The _interesting_ way to do a tachometer would be to
|> measure the ripple itself, thereby avoiding any connection to the engine.

Careful what you mean by ripple. On the average car, the main ripple
(RMS) is from the alternator, not the ignition. The ignition
noise has much faster risetimes, though. Either could be counted
and are proportional to RPM.

-- 
------------------------------------------------------------------------
     Dave Medin				Voice: (205) 730-5812 (w)
  Intergraph Corp.			       (205) 837-1174 (h)
     M/S CR1104
Huntsville, AL 35894-0001	Internet: medin@catbyte.b11.ingr.com

   *********Everywhere You Look...(at least around my office)***********

       *The opinions here are strictly my own (or those of my machine)
From: jeh@cmkrnl.com
Newsgroups: sci.electronics
Subject: Re: HV shocks (was: Jacob's ladder)
Date: 12 Apr 92 21:01:43 GMT
Article-I.D.: cmkrnl.1992Apr12.140143.420
Organization: Kernel Mode Consulting, San Diego CA

In article <7480045@hpfcso.FC.HP.COM>, maj@hpfcso.FC.HP.COM (Mike Jassowski) writes:
> In sci.electronics, pollock@milton.u.washington.edu (Joe Pollock) writes:
>> Keep in mind that these transformers are
>> center-tapped, meaning the mid-point of the secondary is connected to
>> the case (and to ground, if you've wired it correctly).  This means
>> that THE ONE-HAND IN THE POCKET RULE WILL NOT PROTECT YOU.  [...]
> 
> The one hand in the pocket rule is not meant to keep you from getting
> zapped.  No matter how the secondary of a neon sign transformer is
> wired, and how many hands you keep in your pocket, it is always
> possible to get a very serious shock.  [...]
> 
> --Mike Jassowski (maj@hpesmaj.fc.hp.com)

I agree with Mike.  In fact I think you can get a deadly shock from such a
transformer even if you are standing on the semi-mythical dry wood on glass
insulators (do you know anyone who actually works that way?), and even if you
touch the "hot" terminal with only one hand.  It's true that under these
conditions the current has "no place to go", ie no ground path, but there will
still be a very brief current flow as your body "charges up" to the potential
of the hot terminal. 

I have no idea if this amount of current, for this brief time, would be lethal
or not, but I'm not gonna test it!  This isn't a test you get to go back and do
over again! 

Bear in mind that the shock itself doesn't have to kill you to be dangerous. 
The shock may kill or maim by doing nothing more exotic than causing your 
muscles to convulse, throwing you against the wall or onto the floor with 
extreme violence.  (This is a particular hazard when working around TV sets
without discharging the CRT 2nd anode.  The shock itself might not be lethal
but it might cause you to swing your hand into the neck of the CRT, and if your 
hand is holding a tool, there's a good chance of breaking it... and the 
resulting implosion won't be pretty.)

	--- Jamie Hanrahan, Kernel Mode Consulting, San Diego CA
Internet:  jeh@cmkrnl.com, hanrahan@eisner.decus.org, or jeh@crash.cts.com
Uucp:  ...{crash,eisner,uunet}!cmkrnl!jeh
Newsgroups: sci.electronics
From: jeffj@krfiny.uucp (J. Jonas)
Subject: Re: Electrostatic Field Promotes Hair Growth ???
Summary: Hey Moe!
Organization: Jeff's house of computer pieces
Date: Fri, 10 Apr 1992 15:32:22 GMT

>There is currently research being done at the University of British
>Columbia about the ability of ELECTRIC CURRENT in stimulating hair
>growth.

You mean, if I stick my finger in the light bulb socket,
not only will my hair stand on end, but more will grow on end too?

If you look at very old Sear's catalogues, you'll find that
electric belts were a popular item.  The belts had several
electrodes and gave a mild shock from battery power.
After 100 years, little has changed!
Medical quackery still lives on, it's just packaged a little slicker.
From: gkwan@balboa.eng.uci.edu (Greg Kwan)
Newsgroups: sci.electronics
Subject: Re: DS1267 dual digital potentiometer I.C. from Dallas semiconductor
Date: 7 Apr 92 22:24:35 GMT
Organization: University of California, Irvine

In article <1992Apr7.195910.8652@acsu.buffalo.edu> v064mb9k@ubvmsb.cc.buffalo.edu (Neil Gandler) writes:
>Has anyone used the DS1267 I.C. made by dallas semicomnductor in an
>application to control volume in a stereo. The data sheets given to me
>when I received three of these chips in the mail were not too helpfull.
>They gave no example circuit. I payed $18 plus shipping for three of these
>chips it would be a waste of money if I can't use them. Does anyone have
>data sheets on this I.C. that gives an example circuit or does someone
>know how I can use it. Its outputs are clearly described. Showing
>the output as if it were a real dual potentiometer. But the inputs
>are a reset pin, port data input/output and clock input.

I was going to reply directly but am not 100% positive so if I am wrong,
someone please correct me.  Here goes:

Without knowing the exact application, I'm not sure that the DS1267 is the
ideal part to use.  We were using that part (the 10k version, if I remem-
ber correctly) in a product.  It was controlled by a microcontroller (the
MC68HC705C8S) through one of the ports.  Since the DS1267 has linear steps,
an equivalent log table needs to be stored somewhere (e.g. in EPROM) for
it to be used as a volume control.  It is controlled by (serially) clocking  
the new pot values to the serial-input pin (while enabled, of course).  
I don't remember the order of the input bit stream.  On power on, it ini-
tializes at half (-6dB) power.

It is a good part, and we didn't have any problems with it, but you really
need to control it with a microprocessor.  Sorry, I don't have the data
sheets for it anymore (the DS data book had a good description).

good luck,
greg

gkwan@balboa.eng.uci.edu
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Newsgroups: sci.electronics
Subject: Re: Parallel and Serial Ports
Date: 7 Apr 92 03:29:46 GMT
Article-I.D.: uhura.1992Apr07.032946.605
Organization: Northeastern Ohio Universities College of Medicine

Four of the leads on an IBM-PC compatible printer port are
bi-directional in that you can program them as an output then
sample the level as an input to see if the signal really changed.
Products such as Laplink send data in sequences of 4-bit nybbles
taht way.  Ethernet ports and portable HDUs do that too.

For question two, newer v.32 and some 2400 baud modems do
buffering and baud rate conversion.  My computer at home has a GVC
v.32 modem, typical of many in the $350-400 price range.  I run
data into the modem at 38.4Kbuad regardless of what is on the other
end.  The modem can mediate the data flow by sending either
xon/xoff characters or using the RTS/CTS leads.  Obviously, the
terminals in the bar use some sort of flow mediation.  I've seen
very few terminals that can keep up with a 19.2K data stream for
more than a couple hundred characters.

-- 
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu   (140.220.1.1)
From: matas@utkux1.utk.edu (04464PMS)
Newsgroups: sci.electronics
Subject: Microwave design software
Date: 10 Apr 92 12:05:54 GMT
Organization: University of Tennessee Computing Center


           send ten bucks (foreign orders add 5$) to

                Puff Distribution
                Electrical Engineering M/S 116-81
                California Institute of Technology
                Pasadena, CA 91125

       specify 3.5 inch or 5.25 inch diskettes  (IBM compatible)
 
     from the manual "PUFF IS A SCATTERING PARAMETER and layout
calculator for microwave circuits.....After a circuit is laid out on the
screen using cursor keys, a frequency or time domain analysis is
available with a few keystrokes...etc."

    aaron     matas@utkux1.utk.edu
From: jeh@cmkrnl.com
Newsgroups: sci.electronics
Subject: Re: goodbye Heathkits
Date: 6 Apr 92 01:20:53 GMT
Article-I.D.: cmkrnl.1992Apr5.182054.404
Followup-To: sci.electronics
Organization: Kernel Mode Consulting, San Diego CA

Heath is still selling a few kits -- at least according to the catalog I just
got from them.   A 1000W linear amp for hams; the Most Accurate CLock (the
new M.A.C. II is only available assembled); some assorted test gear.  The 
Most Accurate Clock kit and its RS232 interface are still in stock -- I just
ordered the pair.  Couldn't resist, especially knowing that they'd be going 
away soon.  :-)

	--- Jamie Hanrahan, Kernel Mode Consulting, San Diego CA
Internet:  jeh@cmkrnl.com, hanrahan@eisner.decus.org, or jeh@crash.cts.com
Uucp:  ...{crash,eisner,uunet}!cmkrnl!jeh
Newsgroups: sci.electronics
From: f1sami@uta.fi (Samu Mielonen)
Newsgroups: sci.electronics
Subject: WANTED: Mail order source for laser accessories
Keywords: gimme some!
Date: 7 Apr 92 13:40:09 GMT
Followup-To: none
Distribution: inet
Organization: Overkill corp.

I would appreciate any information on mail order companies selling
laser accessories in small quantities. Preferably situated in Europe,
but others will do quite nicely too.


Thanks 	Samu Mielonen, f1sami@uta.fi
Newsgroups: sci.electronics
From: richtt@aix.rpi.edu (Timothy G. Richter)
Subject: Re: question about RC circuits for timing purposes
Organization: Rensselaer Polytechnic Institute, Troy NY
Date: Sat, 11 Apr 1992 02:06:19 GMT

In article <9633.29E50A42@ofa123.fidonet.org> Jeff.Lindstrom@ofa123.fidonet.org (Jeff Lindstrom) writes:
>  I would suggest using a HexFET instead of the transistor.  With no base current, the circuit would work better.
>

What's the difference between HexFETs and MOSFETs?     

-Tim Richter
richtt@rpi.edu

Xref: sparky sci.electronics:8110 comp.dsp:1076 sci.engr.biomed:192 sci.math:5697
From: andrews@rehab.njit.edu (John Andrews)
Newsgroups: sci.electronics,comp.dsp,sci.engr.biomed,sci.math
Subject: quaternians, tracking, 3 dimensions
Date: 7 Apr 92 03:08:14 GMT
Organization: New Jersey Institute of Technology, Newark, N.J.


                   Azimuth Elevation and Roll

                               or

                            X Y and Z

                               or

                        rho phi and theta

                               or

                       yaw pitch and roll

     all three describe the orientation of an object in
     three space, but in different ways. I am told the most
     efficient method of computing the relative position of
     the object is with units of measure called
     "quaternians". Can anyone give me some initial insight
     into what quaternians are, how they are used, why they
     are efficient, and/or how cumbersome the calculations
     of the above directional parameters can be using
     quaternians math?

     This is part of a larger project involving 3-
     dimensional locating and tracking. Thanks for any and
     all responses.

     					-=john



-----------------------------------------------------------------------------
john f andrews                SYSOP           The Biomedical Engineering BBS
    24 hrs             300/1200/2400/4800               (201) 596-5679
-----------------------------------------------------------------------------
INTERNET jfa0522@hertz.njit.edu                                CIS 73710,2600
-----------------------------------------------------------------------------
From: zlau%arrlhq.UUCP@uhasun.hartford.edu (Zack Lau)
Newsgroups: sci.electronics
Subject: Re: Cable losses
Date: 16 Apr 92 20:20:03 GMT
Article-I.D.: arrlhq.576
Organization: American Radio Relay League

From: Jeff.Lindstrom@ofa123.fidonet.org (Jeff Lindstrom)
Newsgroups: sci.electronics
Subject: Cable losses
Date: 14 Apr 1992 11:14:08 GMT
Organization: Universal Electronics Inc. (Public access BBS)
 
U>Shouldn't the long cable attenuate the signal or even roll of the high
U>frequencies?
 
>  It IS attenuating the signal, but too little to notice for the low frequencie
>s you mentioned and the moderate cable lengths you are using.
 
U>How can I determin the maximum cable length before signal degradation begins?
 
>  First, determine an acceptable degradation.  Then look at the specs for the c
>able you wish to use.  The major loss will be distributed capacitance (commonly
> expressed as picofarads/foot or nanofarads/foot).  Multiply by the cable lengt
>h and take the RC time constant from the circuit (can you say Thevenin's Rule? 
> I knew you could.).
 
This isn't the way to do it, because the cable also has distributed 
inductance which cancels out the distributed capacitance.  Incidentally,
cables with a silver plated steel conductor(s) sometimes have much higher loss
than you might expect, because the silver is so thin that skin effect
degrades the lower frequencies.  It has been pointed out to me that 
the actual dielectric losses of both teflon and polyethylene are pretty
much negligible, though this may change if we actually get to see cables
made out of superconducting materials.  For now, the resistive losses are 
of primary interest below 1 GHz.


> Another source for degradation is outside noise coming through the shielding.
 > That will be a function of the shield's construction.
 
___
     Amiga MailMan v0.9
 
 
--  
 
Jeff Lindstrom
Internet: Jeff.Lindstrom@ofa123.fidonet.org
Compuserve: >internet:Jeff.Lindstrom@ofa123.fidonet.org
From: bill@hacktic.nl (Bill Squire)
Newsgroups: sci.electronics
Subject: Re: DC Shock
Date: 12 Apr 92 15:09:58 GMT

berger@atropa (Mike Berger @ University of Illinois at Urbana) once wrote....
>dino@inqmind.bison.mb.ca (Tony stewart) writes:
>>jon@sparcplug.et.iupui.EDU (Jon Burgoyne) writes:
>
>>> I'm looking for a small circuit that could provide a shock to my dog.  This i
>>> to build a collar similiar to the invisible fence product.  I believe they us
>>> a 22.5v bat.
>>> 
>>> The RF part I can probably struggle through but producing a shock was not
>>> something they taught us in school.

>Why does anybody want to help this guy torture his dog?

        I agree with the above and to states and countries that have banned
these things.  A much nicer to the dog and probably as effective way is to
produce a fairly loud 15 to 20kHz tone right at the dog.  I think that will
give him the message!  Shocker things are easy to build, but as long as
this application is in discussion, I'll refrain from giving any ideas!

                                                Bill