waashk/20ng huggingface dataset:
jvannes@vms.macc.wisc.edu writes:.... > >I designed and built hardware in 1988 that would output a logic level (from > >a 567 tone detector) upon detecting a 500 microwatt LED 28 feet away. > >Used a Motorola MRD360, biased linearly  in a DC-feedback loop to servo out > >variations in sunlight (and 60Hz from lights). Used no lenses. > >Allen Sullivan > I would be interested in knowing more about the sensing hardware.  What did > you use for the detector?  Could you detect the angle of location, or did > the system simply respond to the presence of the transmitter in the sensors > field of view?   Phototransistor-> X100 -> X100 -> NE567 with 330Kohm              Limiter  feedback to base                   to control operating point (I expect this really hurts Noise Figure! Any comments from Phototransistor experts?)  We intended to use this atop a stepper motor, to provide headings to the beacons. The plan was to have 3 or 4 beacons, of different frequencies, in  each room, and tell the 567 what frequency to phase-lock to. We did not do so. One challenge was that the available stepper had 8 degree steps! Knowing the headings to each beacon, we would have used the surveyor  technique of RESECTION to determine robot location. (No, I ain't going to explain resection over the net.)
I want to convert a 500 Volt sinewave with frequency between 1 kHz and 10 kHz, to a 10 Volt sinewave with the same frequency, by means of a transformer. The secondary current will be .6 A (600 mA).  What kind of transformer should I use (ferrite?) Can I buy one? If so, I need a partnumber and supplier If I cannot buy one, how do I go about winding one myself? What core do I use, how big must it be in order not to saturate, what thickness copper wire, how many turns, etc.?  I know little about analog electronics, so I hope some kind soul here will help me out. Pointers to relevant databooks will also be highly appreciated.  Thanks,
In article <C5uFIG.1Dv@news.cso.uiuc.edu> martyj@mrcnext.cso.uiuc.edu (martin johnson) writes: >I need a small battery powered hi voltage capacitive discharge supply to >deliver ~6 joules at 250 volts...  the ubiquitous >camera flash circuit is what I want, but I cant get mine apart without >breaking it...  Charlie Brett's suggestion -- buy one of the disposable flash cameras, use the film, then take the thing apart -- is a good one.  Note, though, that you won't get a particularly precise voltage out of such a thing, and it may be a single-point design that won't adapt well to off-nominal operation.  The things are easy to dismantle.  The key piece of information is that when you advance the film on one of them, you are winding it *into* the film cassette -- it is unwound from the cassette in the factory, when the camera is made.  So no darkroom is needed for dismantling.  It's standard film, so just take the cassette in for processing.  All the camera-store people do when you bring in one of the disposables is rip it apart, toss the film cassette into the to-be-processed bin, and throw the battery in one trashcan and the rest of the camera in another.  If you take it apart yourself, you get an AA alkaline battery (still with a fair bit of life in it) and all kinds of little bits and pieces from the camera.  I expect you could even re-load and re-use the camera if you were really determined.
Does anyone know of an FTP site where I might find public domain software for the Motorola 68HC16 microprocessor? I am looking for a basic interpreter/compilier or a 'C' compiler.  Thanks in advance. 					Ed Murashie
Hi Netters!  I am looking for the list of universities in Austrailia, which has electronics department.  I am considering to spend a year for research in Austrailia about communication area.ýé I am interested in Mobile communication areas and spread spectrum communications etc.  But I don't have any information about Austrailian Universities. Can anybody recommend a good university in coûßmmunic÷³ation area? Any comments will be welcomed!  Bye.
Newsgroup: sci.electronics From: martin.vuille@synapse.org Subject: Electronic Design  Does anyone know the telephone number for the circulation department of 'Electronic Design' magazine?  MV
In article <72020037@otter.hpl.hp.com> tgg@otter.hpl.hp.com (Tom Gardner) writes: >What is the difference between vertical and horizontal?  Gravity?  Doesn't gravity pull down the photons and cause a doppler shift or something?
In article <1rbs1e$m6s@insti.physics.sunysb.edu> mmoss@ic.sunysb.edu (Matthew D   Moss) writes: >  > Subject says it all, though I should specify that I'm looking for solutions > that DON'T require me purchasing specific chips, etc.... >  First you find a congenial member of the opposite sex ... >  -- Thomas Clarke Institute for Simulation and Training, University of Central FL 12424 Research Parkway, Suite 300, Orlando, FL 32826 (407)658-5030, FAX: (407)658-5059, clarke@acme.ucf.edu
try finding a friend that has caller id, then give him a call...  jb   In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:     Path: shearson.com!uupsi!psinntp!uunet!haven.umd.edu!darwin.sura.net!newsserver.jvnc.net!howland.reston.ans.net!noc.near.net!nic.umass.edu!risky.ecs.umass.edu!umaecs!alee    From: alee@ecs.umass.edu    Newsgroups: sci.electronics    Date: 18 Apr 93 15:04:10 GMT    Lines: 13      Greetings!  	   Situation:  I have a phone jack mounted on a wall.  I don't 		       know the number of the line.  And I don't want 		       to call up the operator to place a trace on it.  	   Question:   Is there a certain device out there that I can 		       use to find out the number to the line? 	   Thanks for any response. 						       Al   --
In article <1993Apr20.230749.12821@reed.edu>, mblock@reed.edu (Matt Block) writes:  >	I guess what I am saying is that your question is difficult, if not >impossible, to answer.  What exactly do you want to know?  Do you need a good >one for a project you are working on?  How secure must it be?  Are you trying >to crack one that someone else has used?  I can probably make suggestions, >assuming the activity is strictly legal.  (In general, it is a BAD idea, >legally, to tamper with copy protection.  It can also lead to corruption of >files which you necessarily do not have back ups of (being as they are copy >protected,) which can be devestating.)  Do you have absolutely no ideas for >practical applications, and are merely curious? >	Please clear up those questions, and I'll try to help as much as I >can.  May we interpret this as an offer to volunteer as editor for a "Copy protection FAQ" ? I am quite sure that I am not alone welcoming such an initiative! *I* will volunteer to ask some of the questions, if you will provide the answers :-)
In article <1993Apr15.060043.15664@serval.net.wsu.edu> rwilley@eecs.wsu.edu (Ronald Willey - CS) writes: > >	The Supra accelerator that is mentioned in one of the pervious >articles, is not 68000 or 68020 based.  It runs on a 68030 at 28Mhz and  >the design they are using is very simple( if you were referring to the >A500 exteranal model).  Hmm - I don't think you and I are thinking of the same thing. I was the original poster, BTW. The accelerator that I'm talking about almost certainly uses a 68HC000, according to the footnotes in the Supra ad. It only costs $199 list, so I really doubt if it has a 28 MHz 68030 inside.  It's called the Supra 28, or Supra Turbo 28. There's an external A500 model, and an internal A2000 model.  BTW, does anyone know if a 28Mhz 68HC010 exists? -- Griff Miller >  Griff.Miller@waii.com  < use this for email.        *** My opinions are mine, not Western's. ***
I need a small battery powered hi voltage capacitive discharge supply to deliver ~6 joules at 250 volts. This implies a 200uf cap. I have built a very satisfactorily operating version from a MAX641, but do not like the idea of using a $6 single source part. It seems that the ubiquitous camera flash circuit is what I want, but I cant get mine apart without breaking it. I would appreciate receiving the circuit description or a source of one. I have already looked in several electronics circuits handbooks to no avail. Thanx
Subject says it all, though I should specify that I'm looking for solutions that DON'T require me purchasing specific chips, etc....  In other words, is there some sort of neural network circuit I could build after a visit to a local R-Shack?
nhowland@matt.ksu.ksu.edu (Neal Patrick Howland) writes: > >From what I understand about radar dectectors all they are is a passive >device much like the radio in your car.  They work as an antenna picking >up that radar signals that the radar gun sends out.  Therefore there would >be no way of detecting a radar detector any more than there would be of >detecting whether some one had a radio in their car.   >  Unfortunately, you're wrong on both counts.  The most common method of implementing a tunable receiver is to have a local oscillator.  The local oscillator's frequency can be radiated out of the receiver via the antenna unless the circuit is designed and constructed with great care.  For a reference on detecting radios, get the paperback book _Spy Catcher_. The author discovered how to detect radio receivers from their local oscillator emissions back in the *1950s* while he worked for British Intelligence.    -Greg
You can try SGS L6217A, it can achieve 256 current level(microstep), teere is a circuit in the SGS-THOMSON - " Smart Power Applicatio Manual", order code for the manual is AMSMARTPOWERST/1  Best regards,
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes: > >Greetings! >       >        Situation:  I have a phone jack mounted on a wall.  I don't >                    know the number of the line.  And I don't want >                    to call up the operator to place a trace on it. > >        Question:   Is there a certain device out there that I can >                    use to find out the number to the line?
In article <1993Apr27.152314.28798@donau.et.tudelft.nl> ferry@dutentb.et.tudelft.nl (Ferry Toth) writes: >Subject: **** And now serious: E-Magazine ***** >Summary: How about starting a group where scientific articles can be pre-publish >Keywords: Scientific papers, Electronic magazine > >For some time I've been thinking about the possibility of starting a group >where scientific articles can be published (or perhaps just summaries). >Possible advantages would be: >* Free distribution >* Fast acceptance >* Online discussion between authors and readers > >This would be possible with one group with a moderator for publishing the >articles and one perhaps without for discussion.   I think its a great, but idealistic idea. A reseacher will first of all try  to publish a worthy paper in a credible, professional magazine and not in a  community like USENET which is infamous for lots (not all) of junk  information. The papers that will be "published" here will, in general, be  of low quality. Also, it is improbable that any credit will be given to a  researcher who publish here - and sadly, that is nowadays a main reason for  publishing.  USENET is great for informal discussions and free exchange of ideas - keep  it like that. A new, specialist group is just not worth it.
I've just started programming with the PIC16c57 and I'd like talk to similar like minded people ?  Have you built anything interesting, if so, I'd be interested in talking about various aspects.  Yes, I already have the application sheets, assembler & simulator.  Cheers,  Stuart
There is or was a microwave tower next to Florida's Turnpike, and you could watch the cars hit the breaks as they came in sight of it every morning...
In article <1pohuq$4sq@grouper.mkt.csd.harris.com>, wdh@grouper.mkt.csd.harris.com (W. David Higgins) writes: |> I believe the only thing that needs correction, Mr. Vanderbyl, is your |> attitude.  Nope, Mr. Myers has found the bad mistake and posted a correction, thank God.  |> Acting the child won't gain you any favors or make a  Who's acting?  |> positive impression with anybody.  Ghod knows you've make an impression |> on me;  just not a positive one.
Have anyone some idea about how to build a cheap, low resolution (or high :-) video projector...
In article <734953838.AA00510@insane.apana.org.au> peter.m@insane.apana.org.au (Peter Tryndoch) writes: > >If you are going to use one where it counts (eg:aviation, space scuttle,  >etc) then I suggest you go and buy a Fluke (never seen a Beckman), however  >for every other use you can buy a cheapie.  My Beckman died a few days ago, thanks do about a 4 or 5 foot drop onto a lab table.  !@#!@$#!@$@#$  Probably not indicative of anything, but I've already filled out the requisition for a Fluke 87. :-)  Oh yeah, and sometimes our measurements here do count.  Not often, but often enough that I want at least _one_ good meter!
i need to know about the market for cellular antenna technology today... who are the main companies in the market.. how much are they selling them for? who are the contact people?  what are the specs?  I will mail oyou our reserach so far if youcan help us!!
I've come across a circuit from Integrated Circuit Systems Inc called a GSP500.   This chip genlocks a VGA card to a dual input NTSC signal.   The output from this chip is basicly a pixel clock, and has various  speeds.  I notice that it outputs a 28mhz clock..  can this output be  used on an Amiga system? And must it be NTSC/VGA  or can it be NTSC/NTSC  ?   Any simple circuits to boost an NTSC to a VGA signal? Need to genlock a laser disc to my 31khz video. -John
MAMISHEV, ALEXANDER VALENTINO (avm1993@sigma.tamu.edu) wrote: :      Hello,  :  :    Let me introduce a problem: :  :    When I measure a sinusoidal wave (voltage) with a digital voltmeter, using  : AC mode, my output is an rms value (a peak value over 2 squared). / Right? /  :    When I measure a square wave in the same mode (AC), my output is equal  : to a peak value, actually, to the upper flat boundary of the wave. :    I assumed, that a digital voltmeter makes some kind of integration of the  : input value, and divides it over the wave period. / Right?/ :    Now, I used it to measure the same  square wave as above, but distorted  : by high-frequency harmonics. Ideally, output should be the same, but... : The output value was only about 10% of the previous one!  :    Why? What is the nature of this output value? What does the voltmeter  : actually measure? And what does it show?     Re: RMS readings  Unless the DVM *says* it's measuring RMS, it's probably Average voltage. The input is diode rectified and measured as DC.  If it says it's RMS and but measures square/triangle/etc.  incorrectly, it's measuring average and multipling by a correction that's *only* true for sine waves (i.e.  Vave*(0.707/0.63) = Vrms).  If you want correct RMS for (most) any waveform, you need a "True-RMS" DVM/DMM which literally does the Root-Mean-Square calculation in either analog or digital circuitry.  :  :    Related question (less important to me): :    What are advantages and disadvantages of digital voltmeters to compare with  : analog ones?   The last significant advantage of analog (IMO) ** was ** being able to "see" the signal if it was changing over time (e.g.  checking electrolytic capacitors).  Anymore, most DMM have bargraphs, etc. that duplicate this.  :  :    Thank you for your attention, you could mail me your opinion at : avm1993@zeus.tamu.edu or open a discussion here. I would appreciate either  : way. :  :  : Alexander V. Mamishev :  : ____________________________________________________________________________ : Power System Automation Laboratory    <>   phone office (409) 845-4623     : Department of Electrical Engineering  <>   phone home   (409) 846-5850 : Texas A&M University                  <>   fax   (409) 862-2282 : College Station, TX 77843, USA        <>   Internet: avm1993@zeus.tamu.edu : ---------------------------------------------------------------------------- :
olsen@vetmed.cvm.uiuc.edu (Aart_Olsen) writes:  >>|> I noticed at the fusebox that some circuits have the >>|> 12/2 with ground, and that on these circuits, the ground >>|> wire was tied to the same bus as the neutral (white) wire. >> >>This is contrary to the electrical code and should be fixed. >> >Sorry, but this is exactly according to the NEC.
I booked a hotel (Red Roof Inn) last week in Cincinnati (Blue Ash, which is at the northern tip of the metro. Cincy area).  I chose it for a few reasons.   1.  All hotels in and near Dayton were booked solid.   2.  This hotel is only costing $28/night.   3.  It was one of about 4 rooms left on the night I reserved.   4.  Cincinnati probably has more to to at night than Dayton.  I intend       to hit the riverboat entertainment at dusk!  If anyone has other suggestions for nightlife, please let me know of other hot spots.  Thanks!
mdonahue@amiganet.chi.il.us (Mike Donahue) writes:   >I do NOT know much about Adcom Mobil Audio products, but I DO know for a fact >that ADCOM does NOT make its own "High End" Home Audio Equptment and that 80%+ >of it comes directly out of Tiawan...  Like most high-volume manufacturers, Adcom has most of its PC boards assembled off-shore (in their case, mostly in the far east).  Final assembly _and testing_ are done in East Brunswick.  The products are, and have always been, designed entirely in the US; by their own staff and by audiophile gurus like Walter Jung.  Adcom also tends to prefer American and European components over their Japanese/Far East equivalents.  Off-shore assembly is one reason that Adcom is able to make products that perform as well as those from people like Audio Research and Van Alstine (and better than Hafler and Forte'), but at a much lower cost.  Of course, if your musical diet consists mostly of Rock, you might prefer components from Kenwood or Pioneer...
This inelegant device started life as a 175 watt security lamp, until i smashed off the outer glass to liberate the nasty rays, It works a treat, weighs a heap (due to the ballast) , and NO - i wont ship it !! cheers Mike.
Dean Anneser (anneser@pwa-b.uucp) wrote: : My 9 yr old son has signed up to do a science report on batteries.  I was : wondering if anyone could provide me with some information as to how to : construct a home-built battery.  In my grade school days, I remember seeing : the 'ice cube tray' version, but I don't remember what to use as a good : electrolyte or what the easily obtainable metals were.    : Thank you in advance.  : Dean W. Anneser                  Pratt & Whitney Aircraft      : Computer System Specialist       m.s. 161-05                       \__ -\   : (203)565-9372 (desk) 5016 (fax)  400 Main St.               Ooo.. (_)-V/( ) : Uucp:     uunet!pwa-b!anneser    East Hartford, CT  06108    Live to Ride : Internet: anneser@pwfire.pweh.utc.com : "One test result is worth one thousand expert opinions" -- Wernher Von Braun  : --  : Dean W. Anneser                  Pratt & Whitney Aircraft      : Computer System Specialist       m.s. 161-05                       \__ -\   : (203)565-9372 (desk) 5016 (fax)  400 Main St.               Ooo.. (_)-V/( ) : Uucp:     uunet!pwa-b!anneser    East Hartford, CT  06108    Live to Ride  --  The simplest one is easy.  Take a lemon or other citrus type fruit, and stick a pair of metal strips into it for the contacts.  The two strips must be of disimelar metals like copper and zinc.  Then connect a voltmeter to the contacts and read the voltage.  bill@xpresso.UUCP                   (Bill Vance),             Bothell, WA rwing!xpresso!bill
I have never worked with really small signals before and have a few  questions about low level noise.  I have noticed that the waveform  synthesizer that I am using (Analogic 2020) has some relatively large common mode noise on it.  I am using this synthesizer to 'null' out another transient waveform and am amplifying the difference (~200uV) several hundred  times.  The 2020 has about 1-3 mVp-p of common mode noise and this tends to make my measurements hard to repeat.  (The noise is not quite in sync with  line frequency, and on a spectrum analyzer, the main component is about 64Hz).  How can I get rid of the noise?  When I look at the spectrum using an HP 3582A (audio range analyzer), the noise goes away the minute I switch to  'isolation' on the input.  I am guessing the anlayzer has a diff amp on the  input since it will read accurately down to DC.
Martin John Gregory (mgregory@flash.pax.tpa.com.au) wrote: : I've started to look at some devices doing serial data transmission : over fairly decent distances in fairly noisy environments, and have : seen a variety of schemes for protecting the RS232 transceivers (and : the rest of the circuit) from transients on the serial lines.  I'm : left wondering what is the best way of doing this?  How necessary is : it? : [stuff deleted] : What is the wisdom on this out there? :  : Ta, :  : Martin. :  :  From what I know, protection is necessary, esp. if you plan to route the cables into an unknown environment (out of your control). Things like accidental shorts between the signal lines and power cables, or even lightning strikes are very likely and I don't think you like to see the sight of your computer going up in smoke! [Even ethernet cards are protected. I've looked at the one in my PC and the connector is protected by a gas discharge tube!]  {But if you plan to use the serial cables for internal routings (i.e. in controlled environments), it should be reasonably safe not to have them.}  Suggestion: look in the RS data book. They have several RS232 transceivers that have overvoltage protection. Among them include the LT1080, LT1081 and MAX250 and MAX251. The Maxims are suppose to be electrically isolated ones but still need opto-isolators to work (don't ask me why. I've never used them before.  Another alternative is an RS232 surge protector. Two are listed in the RS catalogue. If you need additional info (i.e. stock nos.), just e-mail me.
Just a few comments about the feasability of zipping up a bunch of miles on your electronic odometer with an oscillator....      I wouldn't expect to be able to do this.  Not because the engineers at BMW are putting in anti-fraud logic, but just because an automobile is a noisy, hostile environment for electronics, and I would expect the software to be conservative.     If I were to design a microprocessor-based odometer/speedometer program, it would have the following features ( just off the top of my head ):           * Debouncing/deglitching  ( Is this a real pulse, or just a glitch? )          * Smoothing:  The rate-of-change of speed cannot be too high:                                 This is a car, not an electron.          *  Top speed limit:  Anything above 200MPH is ridiculous: must be                                         electrical noise or contact bounce      As for getting in and presetting the pins:  if this is the circuit board out of a BMW dashboard, I seem to remember a single big chip with lotsa pins in the middle of the card.  Good luck getting at the counter :-).      I wouldn't expect a high input frequency to damage the meter:  remember, it's probably damped so it can't move too fast, and is probably protected.  After all, a car is an extremely hostile place for delicate electronics;  there used to be an app note in the National Semiconductor Linear Databook that went into this in good detail.                                 - Jerry Kaidor ( tr2!jerry@dragoman.com, jkaidor@synoptics.com )