waashk/20ng huggingface dataset:
Recently I posted two oscilliscopes for sale. One has sold, the other is still available:  Used, good condition:  Hitachi V-422 40MHz Dual-Channel Portable Analog Oscilliscope    o 1mV/div    o DC offset    o alternate magnification (10x magnified & non-magnified      waveform)    o VERT mode trigger    o TV sync separation circuit  List price      $910.00 (...and the price Fry's electronics just                          quoted!) :-(  Sells for       $699.99 (JDR MicroDevices current price)                  $745.95 (Products International)  Your price used $425.00 obo ...I haven't gotten an offer at the asking price, so 'obo' applies...  I also have a 'broken' version of the scope which sold:  JDR 2000 20MHz Dual-Channel Portable Analog Oscilliscope    o 5mV/div    o Component Tester (resistors/caps/diodes/coils)    o TV video sync filter    o z-axis input (intensity modulation)  'Broken' means: The CRT produces a nice, bright trace, but the trace does not correspond to the input signal. My guess is it's repairable but more than a simple calibration problem...but I honestly have not tried to calibrate the scope or otherwise fix it. It's 'as-is'. I paid $60 for it in its current state (I bought it thinking I'd repair it, using the 'good' scope for side-by-side comparison...since I've sold the 'good' scope, the 'bad' one doesn't do me much good) and I'd like to recoup that amount. As above, I'll accept offers and take the best one.  I'd prefer a local (Bay Area, California) buyer, so (a) I don't have to ship it and (b) she or he can examine the scope prior to purchase.
Hi.  I was doing research on subliminal suggestion for a psychology paper, and I read that one researcher flashed hidden messages on the TV screen at 1/200ths of a second.  Is that possible?  I thought the maximum rate the TV was even capable of displaying images was 1/30th of a second.  (or 1/60th of a second for an image composed of only odd or even scan lines)
mmoss@ic.sunysb.edu (Matthew D Moss) writes:......... > In other words, is there some sort of neural network circuit I could build > after a visit to a local R-Shack? Marvin Minsky (hi there) writes of building "perceptrons?" in the 1950s using motor-driven potentiometers to vary the weights. He reported that the circuits worked even tho there were wiring errors. (Can you say ROBUST?)  Cadium Sulfide cells vary with light. CMOS or TTL gates provide the SIGMOID somewhat-linear-yet-somewhat-limiter transfer function often used.  Low power Schottky gates, and earlier gates, has about a gain of X8. LEDs probably output enough light to easily control CdS cells, even at a few mA. And paper with dark and light regions, controlled by pencil and eraser, could also control CdS resistance. The very high input resistance of CMOS gates may let you charge up 1uF paper/mylar caps to serve as memory.
1. Can low Voltage lights be controlled with an X10  module by putting it  before the transformer? It seems to work, even the dimmer works. Not very  reliable. Will it damage the module? Can it be done reliably?  2. I put a motion switch (Heath) to a low voltage light, it worked but now it is broken, too much current? How can I get arround that?     3. How can I increase the intensity of a light using the X10 PC computer interface without having it go 100% on first and then down. I am doing my own programing, not the X10 program.
Hey all:  I just moved to NYC and wondered if there are any electronics hackers out there who could point me to places in NYC that sell individual electronic components (switches, pots, transformers, caps, transistors, etc.)  "Radio Shack" doesn't count (they have almost no selection, and their prices are outrageous!)  I have particular interest in audio components (amplifier IC's, power MOSFETS, output transformers, tubes and tube sockets, pan pots, faders, etc.)  I have checked out a lot of 48th street and Canal street so far with no luck.  Am I missing places, looking in the wrong place, or do I have to resort to mail order?
Radio Shack has canceled their "Battery of the Month" Club.  Does  anyone know why?    They say they'll honor existing cards in customer hands, but no new cards will be issued.
In <LHE.93Apr26131014@yang.sics.se> lhe@sics.se (Lars-Henrik Eriksson) writes:  >Most (if not virtually all) swedish exchanges can handle tone >dialling. Many older electromechanical exchanges have been modified >accept tone dialling.   I would not be suprised if the equipment is compatible, in fact New York Telephone (NYNEX) spend a lot of money on Swedish switching equipment recently.  >Lars-Henrik Eriksson                            Internet: lhe@sics.se   You can guess what brand of equipment I refer to :-)  Michael
After I have produced a schematic with PADS-LOGIC, how do I import it into  PADS-PCB to create a PCB pattern?  The only way I've gotten it to work is to output a FutureNet netlist, and then import this into PADS-PCB.  Is there another way of doing this?  I didn't see any information in the instructions provided, but I might have missed something.  Any suggestions would be  greatly appreciated.  Thanks!
In <C5GIA7.7x9@acsu.buffalo.edu> NEIL B. GANDLER     (v064mb9k@ubvmsb.cc.buffalo.edu) wrote:  :>   I am an electrical engineering student and its a must that I get familiar :> with spice. I have been using it and getting used to it but it would :> be great to have a good reference manual that explains everything in an :> organized and concise. I current have "A guide to circuit simulation & :> Analysis using spice". I feel it has the information is just randomly placed :> in the book and its not easy to look up small things when you just :> need a good reference book. I would appreciate any info. Thanks  There is a postscript manual at ic.berkeley.edu in pub/spice3/um.3f.ps directory (about 650kbytes, 126 pages).
In article <1qk4hj$qos@vtserf.cc.vt.edu> prasad@vtaix.cc.vt.edu (Prasad Ramakrishna) writes:  >... Why would the picture tube explode or even smoke?  It's not the picture tube. More likely the flyback. Emerson? can't admire. Han
I've used on-chip capacitors to reduce ground-bounce noise on a small systolic array chip that had 50pF loads on the clock lines. (Design was in 2-micron n-well cmos, using the MOSIS scalable design rules.) Here are some thoughts on the bypass capacitors:  1) They don't help much with simultaneous output switching--there is 	still a large inductance between the bypass capacitor and the 	load capacitor (on both the signal line and the ground 	return), so you still get ground and power line bounce.   2) They do help a lot with on-chip loads, as I had with the high load 	on the clock lines.   3) The transients you are trying to suppress are really high 	frequency, so forget about large areas of poly-thin-oxide-diff 	capacitors, since the RC time constant is too large. 	What I did is to make a metal2, metal, poly, diff sandwich, 	but put a lot of holes in the poly layer, allowing frequent 	diff-metal1 contacts.  I forget exactly how wide the poly 	lines were.  If I were doing this design again, I'd probably 	omit the diff altogether, and use a solid poly sheet instead, 	using just m2, m1, and poly (and substrate, but that has such a high 	resistance it can be ignored at these speeds).  4) You are probably better off trying to tune your circuit to run with 	slightly slower edges and lower voltage swings (especially for 	output signalling), than spending chip area on capacitors. 	I had spare space on the die since the circuit was too big for 	a MOSIS tiny chip, and the next size up was twice as big as I 	needed.   Kevin Karplus --  Kevin Karplus		karplus@ce.ucsc.edu
In article <00969FBA.E640FF10@AESOP.RUTGERS.EDU> mcdonald@AESOP.RUTGERS.EDU writes: >[...] >There are a variety of water-proof housings I could use but the real meat >of the problem is the electronics...hence this posting.  What kind of >transmission would be reliable underwater, in murky or even night-time >conditions?  I'm not sure if sound is feasible given the distortion under- >water...obviously direction would have to be accurate but range could be >relatively short (I imagine 2 or 3  hundred yards would be more than enough) > >Jim McDonald  Refer to patents by JAMES HARRIS ROGERS: 958,829; 1,220,005; 1,322,622; 1,349,103; 1,315,862; 1,349,104; 1,303,729; 1,303,730; 1,316,188  He details methods of underground and underwater wireless communications. For a review, refer to _Electrical_Experimenter_, March 1919 and June 1919.  Rogers' methods were used extensively during the World War, and was unclassified after the war. Supposedly, the government rethought this soon after, and Rogers was convieniently forgotten.  The bottom line is that all antennas that are grounded send HALF of their signal THRU the ground. The half that travels thru space is quickly dissapated (by the square of the distance), but that which travels thru the ground does not disapate at all. Furthermore, the published data showed that when noise drowned out regular reception, the underground antennas would recieve virtually noise-free.  IF you find this hard to believe, then refer to the work of the man who INVENTED wireless: Tesla. Tesla confirmed that Rogers' methods were correct, while Hertzian wave theory was completely "abberant".  ----  ET   "Tesla was 100 years ahead of his time. Perhaps now his time comes."
>   Why does a lead acid battery discharge and become dead (totally unuseable) > when stored on a concrete floor?    When will people learn!  The trouble is the ballast in the concrete and as every fool knows Ballast  resistors are used to discharge batteries. Furthermore it is very silly to  store the battery with the terminals downwards as you must have done to  contact the ballast.   Seriously: self discharge (the actual problem, as stated by others) does vary  greatly with certain types and freaks show low self discharge. I have in  fact seen ordinary automotive batteries which have effectively held full  charge for > 2 years so it must be possible.  If your garage is heated, store the batteries somewhere cooler but above  freezing (flat batteries freeze more easily). Occasionally charge it (once a  month?) or even leave it on 'float' charge permanently (special charger,  DON'T do this unless you know what you are doing, seriously dangerous).  Anouther point is the unsuitability of automotive batteries for things like  electric mowers -- they are not generally designed to be repeatedly deep  discharged and their life may be greatly shorted. Some early zero maintenance  automotive batteries in fact responded to a full discharge with total failure  shortly afterwards but modern ones are superb. (6yrs, 95000 miles and  counting)
In article <1993Apr21.162414.18000@trintex.uucp> elr@trintex.uucp 	(Ed Ravin) writes: >Trans-Am Electronics, Canal Street near 7th Ave -- lots of surplus type >stuff.  They've been out of busines for years.  >Several other electronics or "surplus" type places are still on Canal >Street.  Not any more.  About 2 years ago they all closed. When Ramco/Electronics city closed, it took weeks and many dumpsters to clear everything out (so I heard). There are a few places that sell connectors and phone wires, but no chips, capacitors or discrete stuff.  Sylvan/Wellington is still on Broadway and Canal, but they're not cheap, and not surplus.  It's mostly a TV repairman's store.  -- Jeffrey Jonas jeffj@panix.com --  Jeffrey Jonas
>>: The Ohmite company was the first to characterize resistances by numbers, thus >: our use of the Ohms... > >I don't know about this one, but it doesn't sound right.  DAMN RIGHT it doesn't!  Ohm's come from the greek letter omega, which is used for resistance/impedance.  Of course, the original poster MAY have been being facetious (let's hope so).
Does anyone have some information on the relative fraction of the final cost of each component in an average hard drive?  For instance, I'm pretty sure the heads and the platters are the most expensive parts, with the assembly costs running a close third.  Cost of the electronics is likely in the noise.   Any hard numbers ($$ or percentage)?  Thanks.   +=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+ | Kevin Doherty           E-Systems/Melpar Division   doherty@melpar.esys.com | | Principal Engineer      Falls Church, VA 22046      (703) 560-5000x2659     | +=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+
Sean Oliver (Sean_Oliver@mindlink.bc.ca) wrote: : I live up in British Columbia, Canada.The cable company I use is called : Rogers Cable. Does anyone know of their scrambling techniques, and ways of : getting : around them? Any suggestions of what they might use? :  I don't know the answer to your question, but I am sure Rogers Cable can so I tool the libery of forwarding your question to them and I am sure they will be in touch. :-)
In article <1993Apr25.223611.1@auvax1.adelphi.edu> schmidt@auvax1.adelphi.edu writes:  >platen, etc flew across the room, and several people in the room almost had >heart attacks.  Beware the explosive properties of WD40 vapor. >   We use it as starting fluid for jet ski's. The fact that its a lubricant  works very well since jet ski's are 2 cycle. It also helps when a ski floods with water because we clean the spark plus with the stuff.   OB sci.electronics:   I have an office/studio in my garage with a phone in it. Our wireless phone has a page feature where you can make the phone or hand set ring to get the attention of the other person. Is there a simple circuit that I can use over the second pair of wires (or the first pair) to emulate this effect with the phone in the garage? (ie push a button to make the phone ring in the house or push a button to make it ring in the garage.)    Thanks   Xavier
I am trying to design a small 90mW 472MHz FM transmitter for remote alarm use.  Is there an FM transmitter IC available that can be used for this purpose?  Any help, circuits, info etc will be greatfully accepted.  Please reply to bsc_graham@seqeb.gov.au  Thanks in advance.
I'm a 2600 hacker from The Old Days.  Let's see how much trouble I can get into by telling you what you want to know...   ;-}
In article <1qihcl$9ri@usenet.INS.CWRU.Edu> ae454@cleveland.Freenet.Edu (Paul Simundza) writes: > > >anyone know of any good supplier's of chips, one that could have almost >any chip i need? I don't want to hunt down all the chips I may need so >it would be greatly appreciated if anyone knows of a good distributor >.. >thankyou >  Paul,  Unfortunately, there are not too many retail outlets that'll stock just about every chip made.  The stuff they will stock are the ones that'll sell, like standard DRAM's, 80386's, 68000's, etc,etc. i.e.  I cna't think of any 'one-stop-shopping' store.  The closest you can get is to pick up a copy of Byte magazine or the Circuit Cellar, Popular Electronics, and the like and flip through them.  Distributors like Wyle Electronics, Hamilton Avnet, Pioneer Electronics, etc, etc, don't normally deal with end-users like ourselves where we only a couple of everything...they only deal with people who buy by the hundreds or more.  Each distributor represents and sells a variety of different non-competing manufacturers.  What do I mean by this? Suppose ABC Electronics sells Intel 80386's.  It's a pretty good bet that they won't be selling any of AMD's 386's, or vice-versa. They also can obtain just about *any* chip you want from a manufacturer they represent.  Who knows?  You might be lucky to be able to buy from one of them. But I'd be suprised if you do.  ALso bear in mind that the 1 or 2 qty prices they will charge you will be *much* greater than what a mail order outlet will charge.  My advice?  If you're gonna be designing anything, try to stick with off-the-shelf stuff.  You're going to get stuck if you use too many esoteric parts sooner or later.  good luck,
In article <1pqb8aINN9vg@hp-col.col.hp.com> cab@col.hp.com (Chris Best)   writes: >  > The manual also got into the "cosine effect", wherein the motorist  > always gets the benefit of the doubt (effectively).  Depending on > relative directions of the radar gun and target car, the reading  > will always be THE SAME AS or LOWER THAN the actual speed of the car.   > Never higher. >  > And always remember that the cop doesn't even need radar to ticket you. > His (her?) word as a skilled observer is enough.   The father of a friend of mine is a police officer in West Virginia.  Not   only is his word as a skilled observer good in court, but his skill as an   observer has been tested to be more accurate than the radar gun in some   cases . . ..  No foolin!  He can guess a car's speed to within 2-3mph just   by watching it blow by - whether he's standing still or moving too!  (Yes,   I realize that calibrated guns are more accurate than this, but . . .).    His ability is not that uncommon among people who watch moving things for a   living, I have heard . . ..  So what good is a radar detector except to give you a split second warning   that the guy who just cut you off to pass the guy ahead and to your left   is about to panic stop from 85 on a crowded freeway???
acooney@netcom.com (Alan Cooney) writes: >...discussion of Motorola vs Intel uC's > >In other words, just add your favorite serial level converters (Mac folks >can use the cheaper, farther, and faster RS422 drivers, PC users get to >suffer with RS232...) and start using your project!  Think about it...     How much software is out there for the Mac?  I've been interested in using microcontrollers in imbedded applications for a long time, but was always under the impression that I would need an IBM to run the debug/compile/etc software.    I would like to use a 6811 or 6816.  I'm proficient in 6800 assembly, but have never NEEDED it except some toying with old 6802EVBs.     Motorola doesn't seem to have any information on Mac software (at least their local distributor doesn't) and the ELE department around here has been of little help as well.    I hope someone can tell me that I don't have to buy an IBM to  work with the 6811 or 6816 Evaluation Boards...please send me mail!     Andrew
I am working on a project and am in need of information regarding the   currents (at the head) needed to write to a hard drive and the currents   produced when reading.  If anyone has information it would be much   appreciated. mcole@nmsu.edu
ruck@beach.cis.ufl.edu (John Ruckstuhl) writes:  >I know this is a long shot, but does anyone know what solvent I should  >use to clean duct-tape adhesive from carpet?  May I tease out a sub-thread from this discussion?  Can you all please tell me how to remove  the stickers from new houses' appliances and outdoor lampposts?  Especially the lamppost, right on the glass.  Isn't there something you can rub into stuck-on labels that will release them from their death-grip on glass or other hard surfaces?  Many thanks for any help.                                                  John
In sci.electronics, wayne@uva386.schools.virginia.edu (Tony Wayne) writes: >What is Pink noise and how is it used in sound experiments?      Pink noise has constant power per geometric frequency increment (octave, 1/3 octave, etc).  Thus the 10kHz-20kHz octave has the same amount of noise power as the 10Hz-20Hz octave.     White noise has constant power per arithmetic frequency increment (Hz, kHz, etc).  Thus the 10kHz-10.1kHz band has the same amount of noise power as the 10Hz-110Hz band (both bands are 100Hz wide).     Pink noise can be made by passing white noise thru a -3db/octave filter (usually approximated by a network of several RC pairs). Note: you can't get -3db/octave by using half a -6db/octave network  :-(     Pink noise is commonly used in audio power response measurements. It shows up on audio spectrum analyzers (with octave-related bands) as a flat line across the bands.
In article <1993Apr20.022922.11861@julian.uwo.ca> wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes: >>No restriction was placed >>on receiving RADAR (or, curiously, cordless phones.)  Enforcement >>of the Virginia law is in violation of the FCA of 1934. > >Isin't there some kind of rule (regulation, law, whatever) in some >juristictions that prohibit the use of *police band* recievers >in vehicles?  And that radar transmissions are included in the police band  >so they get covered by the same regulation?  Those rules/regulations/laws would be subject to the same attack:  that they are attempting to preempt federal authority to regulate (or not) radio communications.  Of course, as the original poster noted, court challenges of this kind can get expensive.
Taft Electronics, 45th Street between 5th & 6th -- the only one left in what was once an entire district of electronics stores.  A little expensive.  Trans-Am Electronics, Canal Street near 7th Ave -- lots of surplus type stuff.  Several other electronics or "surplus" type places are still on Canal Street.  I think Bronx Wholesale Radio is still in business -- Fordham Road not too far from Arthur Avenue in the Bronx.  Also in the Bronx is NorthEastern (or was it Northwestern?  Northeast Electronics?) on Jerome Avenue near Bedford Park Boulevard.  They're mostly a TV parts supply house, but when I was building CB radio projects, they were quite handy..
In article <199304251131.AA08572@dec3100a> shiekh@ictp.trieste.it (Andy Shiekh) writes: > >  I have seen the existance of electronics solder with a 2% silver >content that seems to have good wetting and fatique reatings. >  Can anyone tell me why it is not used? (silver is not such an expensive >metal). > From "Management of Electronics Assembly" (Ian Oakes) After talking about 63/37 tin lead alloy and the eutectic point... "Occasionally, impurities may be added to solder, to vary charactersitics  within the soldering process in an attempt to improve performance.  For example, addition of small quantities of antimony and copper can reduce the amount solder moves under stress when solid.  For particular applications additions of impurities may be warranted but, in general, it is best to keep the solder used in a soldering process as pure as possible."  I guess this is the good oil for commercial operations, but it doesn't mention anything esoteric.
I am having trouble obtaining the specified standby current drain from a MC146818A Real Time Clock.  Has anyone out there had some experience in doing this?  The specs call for a few sequences to be met before standby mode is activated, and are a bit hard to decipher on that, but I thought that I had it worked out.  However, with a 32kHz crystal the lowest current drain I can acheive at 3.7V Vcc is 150uA.  This is three times the specified MAXIMUM under the conditions I am attempting to create.  I have done the following things:  1) Made sure that RESET/ is asserted for Trlh after powerup, and AS is    low during this time.   2) Made sure that there is a cycle on AS after the negation of RD/ or    WR/ during which STBY/ was asserted.  What am I doing wrong?  Thanks very much,
In article <beerb.9.0@ccmail.dayton.saic.com>, beerb@ccmail.dayton.saic.com (Bradlee Beer) writes: > I'm interested in buying or building an omnidirectional antenna for the  > commercial FM band (88-108MHz).  The commonly sold ones are a folded dipole  > bent in an "S" shape; and one with a pair of crossed dipoles.  I don't see  > either of these designs as exhibiting any gain, and they probably aren't  > truely omnidirectional. >  >  > I'm intrigued by the discone antenna.  Does anyone have detailed information > on how to design one for the FM band (with 75-ohm impedence)??  Is one > commercially available??  Are there other designs that have GAIN??   >  > I already own a 10-element FM yagi.  It works great, but requires frequent  > rotation for those distant stations.   >  > Brad Beer,  4414 Castle Gate Drive,  Beavercreek, OH  45432-1814  Brad,    For an antenna, gain is synonymous with directionality.  The only way  to get gain (>1) out of an antenna is to design in directionality. The  "gain" of an antenna is defined as the signal increase (for a preferred  direction) over the signal obtained by an isotropic antenna.