waashk/20ng huggingface dataset:
erickson@azure.nmt.edu (Alan Erickson) writes:  > 	I'm trying to bring in 8+ bits to a PC, and would like > 	to use interrupt-driven routines. Without buying an IO > 	board or making a new port, _where_ can I bring in these > 	bits? LPT seems to have only a few inputs, but I've heard > 	rumours that some LPTs have bidirectional lines. Anybody > 	know fer sure? If any bi-d LPTs, which boards have them > 	(I'll be running a new 386DX-33)?            Yes, it is possible.  I'm making a 7 stepper controller board,  with 7 digital inputs, and (up to) 18 digital outputs from the // port.    One main thing that will tell you whether the // port is  bi-directional or not is the bus tranceiver on it.  Look for a chip  numbered 74LS245.  If you don't have this, then it's probably a 74LS244,  which will do you NO good for reading in.              Now, if you do have the '245 then do the following:   First, find the address of the port, (decimal) either 888, or 632.   In pascal, you would "Write(Port[xxx]);" where xxx is the address in  either hex or decimal.  The status lines, pins 14, 16, 17, as well as the  strobe, pin 1, are bi-directional lines, and are read by base address +2,  so for 888, to read from status, then read from 890.  You can also output  to these lines in the same fashion as to the data lines.  In pascal,  do "Port[xxx]:=value ".                   Hope this helps.         Let me know if you need more help.       _________________________________________________   Inspiration  |   ___                             |   comes to     |  \   o  baden@sys6626.bison.mb.ca |   those who    | (  ^  ) baden@inqmind.bison.mb.ca |   seek the     |   /-\      =] Baden de Bari [=    |   unknown.     |                                   |
Do you know if there is an airport nearby? They may just be markers to tell pilots of small planes that there are power lines nearby.
MJM>HI, I was wondering if anyone would be able to help me on twwo related MJM>subjects. I am currently learning about AM/FM receivers and recieving MJM>circuits. I understand a lot of things ,but a few things I am confused MJM>abuot. The first is the MIXER, to mix the RF and local oscillator MJM>frequencies to make the IF. Does anyone have any cicruit diagrams (as MJM>simple as possible) for this kind of mixer? I have come across a MJM>MC-SBL mixer chip But I have not been able to find it in any catalogs MJM>(ACTIVE,etc...)  MJM>Along the same note, are there any SIMPLE fm receiver circuits anyone MJM>may have stashed away somewhere and they couold let me see?.  MJM>P.S. any REALLY GOOD BOOKS on AM/FM theory ALONG WITH DETAILED MJM>ELECTRICAL DIAGRAMS would help a lot. MJM>I have seen a lot of theory books with no circuits and a lot of MJM>circuit books with no theory, but one without the other does not help.  Digi-key has the NE-622 chip which has a local oscillator and mixer on one chip.  For a great combination of theory with actual circuits, the best reference for non-engineers is probably the Radio Amateur's Handbook from the ARRL.  Most library's have it in the reference section.    * SLMR 2.1 * If ignorance is bliss, why aren't there more happy folk?
> This is not a new idea.  At least 10 years ago I got this little gadget with > a keyboard on the back and 8 LED's in a vertical row on the front.  It has a > long handle and when you wave it in the air it "writes" the message you typed > on the keyboard in the air.   ----------  This is not news.  In fact it's where I got the idea from, since it was such a neat item.  Mattell made it, I believe, modeled after a "space  saber" or "light sword" or something likewise theme-y.  My addition was  using a motor for continuous display, and polar effects in addition to  character graphics.  I should have protected it when I had the chance.   No one to kick but myself...
Hi there  Does anyone know how to get hold of data as well as stock of the LCD displays used in the NINTENDO GAMEBOY handheld TV game machines?  Any information wouold be MOST appreciated.  Please e-mail any replies to   arawstorne@eleceng.uct.ac.za  thanks
In article <1qids1INNebl@chnews.intel.com> crichmon@sedona.intel.com (Chris Richmond) writes: > >In article <1993Apr14.193122.20818@mprgate.mpr.ca>, vanderby@mprgate.mpr.ca (David Vanderbyl) writes: >> In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes:  >> |> I'm considering modernizing some old wiring in my home, and >> |> I need a little advice on outlet wiring.  Several outlets >> |> are the old 'two prong' type, without the ground.  Naturally, >> |> the wire feeding these outlets is 12/2, WITHOUT the ground >> |> wire.  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.  >Well, my house was built just last year, and the breaker box is wired the >same way.    	There SHOULD be a connection of the GROUND wire to a ground in the breaker box.  There also should be a connection of the NEUTRAL wire to a ground in the breaker box.  There should be no other  place in the building where such a connection occurs (i.e. not in any of the outlet boxes).  	The NEUTRAL (white) wire is a 'grounding conductor' for the plug, and is NOT safe to touch, while the GROUND (green) wire is a 'protective ground' and carries no current unless some kind of electrical fault has occurred.  It's safe to touch the protective ground, but not to touch the  grounding conductor (because there is current in the grounding conductor, its outlet-box end will not be at the same ground potential as its breaker-box end).
In article <msf.734832494@skaro> msf@skaro.as.arizona.edu (Michael Fulbright) writes: >I am trying to build a synchronous demodulator and I've hit a snag. >In my application I want to be able to change the gain of an >op amp amplifier from 1 to -1, controlable via a digital input. >The most obvious way I've come up with is to use analog switches >to adjust the gain of the op amp. The only analog switch I have >experience with it the 4066. Unfortunately I want to switch an >AC signal which goes from about -5V to 5V, and the 4066 is only >for positive signals. >[...] > I have a carrier signal which varies between 0V and +5V. I want >to demodulate an input signal by feeding the input signal thru a >amp with a gain of 1 when the carrier is at +5V, and thru a amp >with a gain of -1 when the carrier is 0V. The output is then >low pass filtered. I believe this is called lock in detection as well >as synchronous demodulation.  Look at the 4053.  This is a triple 2-to-1 transmission-gate analog multiplexer, with positive and negative power supplies (can be run from a single-ended supply as well).  With dual supplies, the logic inputs still range from ground (0 Volts) to VDD.  This is a neat (well, I think so) design for a switchable-polarity amplifier:                   +-----/\/\/\-------+                  |                  |                  |    /--------\    | INPUT -+-/\/\/\--+----| -      |    |        |              |  opamp |----+------- OUTPUT        +-/\/\/\--+----| +      |                  |    \--------/                  | CONTROL	---------X (analog switch)                  |                  |                 ---                 GND  All resistors are equal-value.  When the analog switch is closed, the amp is inverting-gain-of-one.  With the switch open, it is non-inverting-gain-of-one.  You can clean up the circuit to trim out input offset current if this hurts the balance (this would show up as carrier feed-through).  For high frequencies, the slew-rate of the opamp might cause problems, especially if it isn't symmetrical (and it usually isn't).
I have a stereo compressor-limiter by  Audio Logic (Model MT-66).  The gates work, but the compressor seems to be gone on one channel, and very weak on the other.    I'll probably need an ocsilloscope to trace it down (no pun intended), but if any one with experience with this type of equipment could point me in a certain direction as to where the  circuit is most likely to fail, I'd sure appreciate it.   --  Robert C. Stephens		rob@dexter.psych.umn.edu
I would like to be able to amplify a voltage signal which is output from a thermocouple, preferably by a factor of 100 or 1000 ---- so that the resulting voltage can be fed more easily into a personal-computer-based ADC data acquisition card.  Might anyone be able to point me to references to such circuits?  I have seen simple amplifier circuits before, but I am not sure how well they work in practice.  In this case, I'd like something which will amplify sufficiently "nicely" to be used for thermocouples (say, a few degrees accuracy or better).
victor@inqmind.bison.mb.ca (Victor Laking) writes:  )Do you know what frequencies chanels 17 to 19 use and what is usually  )allocated to those frequencies for broadcast outside of cable?  17 is air comm. 18 is amateur 19 is business and public service
I'm doing sound for a couple of bands around here and we need Direct Input boxes for the keyboards.  These are the little boxes that take a line level out of the keyboard and transform it into low-Z for the run to the mixer.  Sadly they cost like $50 (or more) each and I'm going to need like 5 or 10 of them!  I looked inside one (belonging to another band) and it looks like just a transformer.  Does anyone have any plans for building them?  Perhaps in Anderton's "Electronic Projects for Musicians" book (which I am having a hell of a time tracking down...)?  Thanks a lot!  .s.  PS: Post or email.  I read this group...
In article <734953838.AA00506@insane.apana.org.au> peter.m@insane.apana.org.au (Peter Tryndoch) writes:  >MC>Aye, there's the rub -- if you draw enough current to light an LED, th >MC>equipment at the phone company will think you've gone off hook. >MC>In the on-hook state you're not supposed to draw current.   > >Ok lets have some calculation here: Going by Australian standards, which I  >presume might be similar to other countries ( If not, lets have some  >input) a phone uses 600ohm to loop a 48V line = 80mA. A standard LED  >drains 20mA. So what is the actual loop current required for an "off hook"  >indication, do you know?  Up to 60 microamperes  =   on hook  Over something like 10 mA  = off hook  In between = defective line, and the phone company comes looking               for leaky insulation.
Hi all,  I think the subject says it all - does anyone know how to take the rgb/h/vsync from a standard vga connector and record them on video tape??  Any help is appreciated!   Mark J Cargill
In article <1993Apr15.212629.1834@cmkrnl.com> jeh@cmkrnl.com writes: >In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes: >> I'm considering modernizing some old wiring in my home, and >> I need a little advice on outlet wiring.  Several outlets >> are the old 'two prong' type, without the ground.  Naturally, >> the wire feeding these outlets is 12/2, WITHOUT the ground >> wire.  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. > >They are supposed to be connected together at the breaker panel... but nowhere, >repeat NOwhere, else.  (Well, almost.  There are strange exceptions for things >like sub-panels.) > > >	--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA >Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055 >  Not even in sub panels!  The only place the neutral should be connected to the ground is in a SERVICE DISCONNECT!  In your house the "main" panel serves as the service disconnect.  Sub panles in your garage or workshop for example must maintain seperate neutral and ground busses because they are not  service disconnect equipment.
In article <93114.142835U19250@uicvm.uic.edu>, <U19250@uicvm.uic.edu> writes... >Can anyone offer a suggestion on a problem I am having? >I have several boards whose sole purpose is to decode DTMF tones and send >the resultant in ASCII to a PC.  These boards run on the serial interface. >I need to run * of the boards somwehat simultaneously.  I need to be able to ho >ok them up to a PC>  The problem is, how do I hook up 8+ serial devices to one >PC inexpensivley, so that all can send data simulataneously (or close to it)? >Any help would be greatly appreciated! >Abhin Singla If you can modify the design of the DTMF decoder, the ideal comunications would be over a multi-drop system, like RS-485.  RS-485 boards are available for PC's, probably cheaper than a bunch of RS-232 channels, and RS-485 is cheaper to build onto your satellite modules, using only a single supply 8-pin DIP driver chip.  Software at the PC end would be similarly complex for either RS-232 or RS-485, in my opinion.  The higher data rates possible with RS-485 would permit quasi-simultaneous data transmission. Hope this helps.
OK I sold all but these, I had some offers and I accepted an offer of 25.00 for the pair from bdale@gag.com ( Bdale Garbee ).  I don't know what happened to him but he won't reply now that I accepted it so I'll offer these again. >  > PLease take these and use them.  Take advantage of me... I really > don't know what they are worth. >  > Qty 2  -  Canoga Perkins Fiber Optic Modems, Model 2250, RS-422 >           Interface, appear new.  I have powered up but that's all, >           I have not used them and I cannot tell you whether they >           work or not.     >                                  Make Offer......... >  > Thanks and please buy this stuff or it goes out the door >  > Mack > mdgoodma@cbda8.apgea.army.mil > ..
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? >        Thanks for any response. >                                                    Al  There is a number you can call which will return a synthesized voice telling you the number of the line.  Unfortunately, for the life of me I can't remember what it is. The telephone technicians use it all the time.  We used to play around with this in our dorm rooms since there were multiple phone lines running between rooms.  sorry!
In article <C5usK6.H2H@athena.cs.uga.edu> mcovingt@aisun1.ai.uga.edu   (Michael Covington) writes: > 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... >   Funny . . . I and most of the detector-owning friends I have, are   generally able to *REMEMBER* such things as nearby microwave towers and   radar detectors going off in EXACTLY the same spon EVERY DAY . . ..  I know on I-64 at the Grayson, KY exit, there's a store just off the side   of the road (think it's a Liquor store . . .) with what must be a security   system that would make most federal prisons proud.  It's the only thing   I've ever driven by (besides a cop) that puts my Whistler in "Oh my God   he's Right Behind You!!!!" mode . . ..  I simply ignore the detector and   use my eyes when I drive by that store . . . 40 seconds later, all's quiet   on the front and no problem.   :-) :-)
In article <canright.734829385@convex.com> canright@convex.com (Robert Canright) writes: |you might try |"Computer-Aided Circuit Analysis Using SPICE" by Walter Banzhaf, |at bookstores, paperback, ~$33, lots of examples. Dr. Banzhaf |is a teacher.  Is there another book.  I have this one and don't find it helpfull in  learning Spice.  It would make a good reference book but I found it lacking for learning Spice.  Are there any others?  Craig
FYI:  The actual horizontal dot placement resoution of an HP deskjet is 1/600th inch.  The electronics and dynamics of the ink cartridge, however, limit you to generating dots at 300 per inch. On almost any paper, the ink wicks more than 1/300th inch anyway.  The method of depositing and fusing toner of a laster printer results in much less spread than ink drop technology.  It doesn't take much investigation to see that the mechanical and electronic complement of a laser printer is more complex than inexpensive ink jet printers.  Recall also that laser printers offer a much higher throughput:  10 ppm for a laser versus about 1 ppm for an ink jet printer.  Something else to think about is the cost of consumables over the life of the printer.  A 3000 page yield toner cartridge is about $US 75-80 at discount while HP high capacity (~500-1000 page yield) cartridges are about $US 22 at discount.  It could be that over the life cycle of the printer that consumables for laser printers are less than ink jet printers.  It is getting progressively closer between the two technologies.  Laser printers are usually desinged for higher duty cycles in pages per month and longer product replacement cycles.
Does someone sell OEM scale units with either analog or digital output? I need something like the scales used in supermarket cash registers,  with a dynamic range of a few pounds and reasonable accuracy.  Any sources ?        -David
In <C5JJJ2.1tF@cmcl2.nyu.edu> ali@cns.nyu.edu (Alan Macaluso) writes:  >I'm looking to build a microphone preamp that has very good low-noise characteristics,  large clean gain, and incorportates phantom power (20-48 volts (dc)) for a PZM microphone.  I'm leaning towards a good, low-cost (??) instrumentation amplifier to maintain the balanced input from the microphone, for its good CMRR, internal compensation, and because i can use a minimal # of parts.    >Does anyone out there have any experience, suggestions, advice, etc...that they'd like to pass on, I'd greatly appreciate it.   >--- >A l a n  M a c a l u s o		 	PURPLE MOON GIANTS >ali@cns.nyu.edu  				158 E. 7th. St. #B5 >(212) 998-7837					NYC  10009 >						(212) 982-6630  >		   Without doing anything really tricky, the best I've seen is the Burr-Brown INA103. Their databook shows a good application of this chip as a phantom power mic pre.  >	         --
In article <C5nz60.99z@scraps.uucp>, frankh@scraps.uucp (Frank Holden KA3UWW) writes: > In <C57zsC.9FL@news.cso.uiuc.edu> rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes: >  >>I'm looking for an IC that will convert RS232 voltage levels to TTL voltage  >>levels.  Something relatively inexpensive would be nice, too.  Anyone have >>a suggestion??  Thanks. >  > Well it looks as if Digi-Key sells a chip with the number ICL232 that does what > you want.  They are selling it for about $3.50...   Digi-Key also sells Quad Line Receivers, parts DS1489AN (68cents) and DS1489N (48cents).  A Quad Line Driver, part DS1488 (48cents), is also sold.  I guess if you don't won't to supply +12V, the chips with the pump-up circuitry might be worth the extra cost.  But 1488's and 1489's are available at your friendly neighborhood RS, parts MC1488 (276-2520) for $1.29 and MC1489 (276-2521) for $1.29.
I don't know much about Hydrophones, so I'm looking for any information that will help avoid problems I haven't thought of! I would like an  inexpensive hydrophone and amplifier with tape (line level) outputs... something like Edmund sells for $250. They also sell just the microphone (hydrophone) head for $24, but how does one construct the enclosure? Any information would be greatly appreciated, Thanks!
In article <1r53r8INNq0i@gap.caltech.edu>, franko@cco.caltech.edu (Frank Filipanits) writes: > > > Can anyone tell me where it is possible to purchase controls found > > > on most arcade style games.  Many projects I am working on would > > > be greatly augmented if I could implement them.  Thanx in advance. >  > >HAP controls just outside Chicago sells these. > >						Andrew MacRae >  > Actually, it's HAPP, and some of their equipment can be found in the  > Parts Express catalog (1-800-338-0531).  They show switches for $2, > joysticks for $13 and trackballs for $80.  They also have pinball parts.   You're right, it is HAPP Controls, Inc., but you can buy direct from them.  I don't have a phone number with me, but anyone interested in it can email me for it.  I don't remember their button price, but the joystick price was $8.95 per dozen at last check.  Should be slightly higher for one or two, but cheaper than Parts Express.  As for the trackballs, i don't know the new price either. But I can sell you rebuilt arcade trackballs for $50.  That includes new rollers and new bearings (when nec.).  I also have a pile of used joysticks and buttons that i would be willing to sell.  Please email to address below if interested.  --Donnie
Has anyone ever heard of FET-TRONS (or is it FETRONS, FETTRONS, ...). These were FET replacement modules for vacuum tubes. I'm looking for applications where they were used.
In article <1993Apr16.142715.12613@sol.ctr.columbia.edu> seema@madvlsi.columbia.edu (Seema Varma) writes: >Getting a custom-made package is too expensive, so >I am trying to choose between a flatpak and a >leadless chip carrier. The flatpack would be hard >to test since it has to be soldered on to the test >setup and I would spend loads of time soldering  >as I kept changing the test chip. The leadless chip >carrier sockets also have long lead lines and may >not work at high speeds. >  >	Does anyone out there have experience/knowledge >of this field ? I would greatly appreciate help! Any ideas/ >names of companies manufacturing holders/sockets/packages >would help.   Check with Kyocera America, Inc.            24 Prime Park Way, Suite 150            Natick, MA 01760  They are one of the largest manufacturers of IC packaging in the world.  It sounds like you would be a good candidate for wafer probing or at least IC probing to test performance.  HP, Cascade Microtech and Tektronix should be able to help you here.  One note, testing at high frequency accurately can be an *expensive* business.
In <C57zsC.9FL@news.cso.uiuc.edu> rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes:    >I'm looking for an IC that will convert RS232 voltage levels to TTL voltage  >levels.  Something relatively inexpensive would be nice, too.  Anyone have >a suggestion??  Thanks.   Well it looks as if Digi-Key sells a chip with the number ICL232 that does what you want.  They are selling it for about $3.50...  Hope this helps... Frank  --   ************************************************************************** * Customer asked "What's that thing?".                                   * * I answered chuckling "Well, it's a highly technical, sensitive         * * instrument I use in computer repair! Being a layman, you probably      * * cann't grasp exactly what it does. I call it a B.F.H.....              * * Frank W. Holden - KA3UWW - "The Radio Doctor"                          * * - - - - - - - - - - - - - - - - - | - - - - - - - - - - - - - - - - -  * * SnailMail:                        | Inter-Net:                         * * 685 Addison St.                   | frankh@scraps.pittsburgh.sgi.com   * * Washington, Pa. 15301-5601        | Packet:ka3uww@n3idi.#wpa.pa.usa.na * ************************************************************************** DISCLAIMER:<disclaimer.h> - I confess, you did it!!! --
In article <C52DsD.7pB@compsci.liverpool.ac.uk> scst83@csc.liv.ac.uk (Chris Smith) writes:  > I'm looking to build a DSP for guitar processing. Hence lots of background > information would be really useful ! >  > If anyone's got any info, could they email.....  Well, I'm not sure I'd use this to process a guitar but there was a audio filter DSP construction article in the Sept 92 issue of QST magazine (Ham Radio oriented).  The DSP is available in kit form for about $120.  This particular DSP filter was targetted toward processing audio to remove noise (static).  I built it and it really works well.  The source code is available too.  It makes a noisy audio signal much easier to hear.  Note that this is for communication applications and is not "high fidelity".