waashk/20ng huggingface dataset:
In article <1993Apr21.081317.599@das.harvard.edu> squish@endor.uucp (Shishin Yamada) writes: >The Atari 2600 used a 6502 CPU, just like their entire 8-bit line >(400, 800,1200,1400, 1440, 130xe, 65xe computers, as well as the 5200 >game machine).   Wrong, it has a 6507.  >The 2600 had some extra ASIC chips that were basically >modified graphics chips and PIA's for the joysticks.   It had one custome chip (not an ASIC in the sense that word is now understood): the TIA (sometimes known as the 6526, although most other manufacturers list that as the CIA complex interface adapter.)  TIA stands for Television Interface Adapter, and it handles sound, paddles and the minimal video hardware the 2600 possessed.  There was also a standard 6532 RAM, I/O, Timer (RIOT), plus a voltage regulator and (if memory serves) a 555 timer.  That's all.  >Later model 2600 >might have incorporated many of the chips into one ASCI, as the weight >of the machines and part count decreased a lot over the years.  Not according to the servicing documentation I have here.  The 2600 did not change intenally very much at all.  >Additionally, I think the 2600 used 2K, 4K, and up to 8K of ROM for >their games.   ROMS were mapped into the upper 4K of the 6507's address space.  2K and 4K games were fine, but later 8K and 16K games needed bank switching.  Atari (and others) made much of these "huge" cartridges.  >I have no idea how much RAM it had to work with, but I >would hazard a guess of 2 or 4K RAM.   Wrong, it had 128 bytes of RAM from the RIOT.  This was multiply mapped into both page 0 (pseudo-registers) and page 1 (stack), and also throughout the bottom 4K of memory.  TIA registers also sat in this address space.  As 128 bytes of RAM was somewhat limiting, some later cartridges also carried RAM themselves, which was interesting as Atari had provided no write line to the cart.  This was managed by mapping the reads from RAM into one address range, and the writes into another, but all the time this scheme ate into the *very* scarce ROM address space.
Inkjet and Bubblejet printers are the same tech.  "Bubblejet" was trademarked by Cannon and inkjet was by HP I belive.  I have seen both, and own a  "bubblejet" (a Apple StyleWriter which has a cannon engine) with a 360 dpi rated output.  The output is very good with quality paper, which is very importaint.  Cheap paper gives bad results.  I use sealed paper and the only differenc is that the ink is less dark than toner (I compaire to the Apple Personal LaserWriter NTX), but then again the difference is $300 to $1500 so....
In <1qmbi7$aln@transfer.stratus.com> Michael_LaBella@vos.stratus.com writes:  >I gather by off-shore assembly you mean that adcoms are built by  >blue-fin tuna's who are into that squid-fi sound?  (I agree on that one).  >My Adcom 555 preamp did sound better after installing the famous   >"running the chips class "A" resistor mod", and replacing the metal  >bottom cover with plexiglass,, too bad the factory could not make em sound  >better,, but better sound, unfortunately, does not appear to be a priority  >with Adcom, else the mods would neither have been necessary, nor would they  >have improved what was already touted as superlative state-o-d-art le'sound.  >I really want to hear from all those people out there who have traded up   >from an sp9II (even an sp3a!) to a GFP-555/etc., or maybe from those that  >have dumped their forte' amps for a GFA-555/etc....      I am one of those folks who traded UP from a 500 to an Audio Research SP9 II!  :-)
Motorola has a good app note on a 10 band equalizer using a 56000 DSP. It could be easily ported to an Ariel board, or even a Turtle Beach 56K development system.
Hello there.  The other day I was feeling a tad nostalgic and thought about constructing an old-time crytal radio set.  I figured on substituting a modern germanium diode for the crystal, and winding the antenna coil, etc., myself.  The only problem I seem to have is in locating a source for a tuning capacitor -- you know, the old meshed-plate variable condensers which used to be the mainstay for tuning circuits.  Well these things seem to be all but extinct in their original catalog habitats.  Trimmer capacitors are relatively abundant, but are not really suitable for this application.  So, can anyone point me to a supplier of tuning capacitors in the  0--360 pF range?  Manythanks.  --
In article <NURDEN1.25.734866568@elaine.ee.und.ac.za> NURDEN1@elaine.ee.und.ac.za (Dale Nurden) writes: >I'm wanting to build a simple UPS for my PC. ... sustain the computer long enough to complete  >the current task and save, 5 to 10 minutes should be enough.... >I think, though I don't really need to keep the monitor active (I can try to  >remember what to do) so maybe I can avoid a DC-AC inverter and just use a  >battery to directly supply the motherboard and peripherals.  Now there's a good idea ! All you need is 20 amps DC for a few minutes, and a good (wetware) memory (was I using wp or autocad or ...). I thought of the same idea myself a few days ago. I've got a fairly new car battery that I take along in my 4x4 when I go camping, and it sits around useless when I'm home. I wish I could get a batteryless ups to use it with, or use it with a heavy duty 5-volt regulator to supply the PC. But I guess you'd need -5v and -12v  (and +12) too (2 more batteries ?).  An alternative would be to leave a 40 AMP battery charger hooked up to the battery and run a 12vdc to 110vac converter running all the time, and when the power goes out, voi-la ! the 110vac converter keeps on running off the battery ! and then I could take the 110vac converter and my computer on the camping trips !-)
In article <1993Apr23.102039.1720@mala.bc.ca>, wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus) writes: >  > The color of the board shows the composition of it, hence the use of it. >  > Original and older boards were bakelite composition, and were brown. > Phenolic (spelling) was a tan > Most "non filled" fiberglass boards used in computers are green. > Filled fiberglass is blue. > Teflon is white. >   Rubbish. The reason for the colour of the boards depends on the solder mask that is used. Older boards (bakelite and phenolic) rarely used a solder mask (these boards are not suited well to automatic stuffing and soldering techniques) and hence are the colour of the compound used to make them. These days boards are made of fibreglass for most general purpose uses and have a solder mask applied to them to prevent close traces shorting to one another during soldering (and also to prevent the decomposition of traces under harsh environments). The light and dark green boards ofter seen have a "dry film" mask applied to them (usually applied as a complete film photographically produced). The blue (and red or orange) boards are a two-part epoxy or a liquid-imageable resist formulation and are applied in a different manner. There's a lot of info about the pro's and con's of each, but that's another story...      Sla/n go fo/ill,                     Risky B.
If you want to try a non-toxic solvent, there's one made of citrus that  works very well and doesn't take your skin off in the process.  One brand  name I've used is Citra-Solve, but there are others too.
>>> On benzene and acetone. Not only is benzene a carcinogen, it is adsorbed through the skin and cause cumulative damage to the bone marrow which is essential to the production of your blood cells.  It is highly toxic. One exposure is unlikely to kill you, but it will likely do hidden damage.  Benzene is one compound that chemists try like hell to avoid using! Acetone is much less toxic, but is highly flammable and volatile.  It also dissolves lots of things so handle with great care!
In article <2745@snap>, paj@uk.co.gec-mrc (Paul Johnson) writes: > >I was having a look through a couple of components catalogues when I >came across a range of Peltier Effect heat pumps intended for cooling >components.  For those who have not heard of this effect, you put a >current through one of these devices, and it pumps heat from one side >to the other.  Reverse the current and you reverse the effect.  I >think a temperature difference can give you an EMF as well. > >Anyway, it struck me that you could make a nice cool/hot box for >picnics with one of these, a power regulator, a thermostat and a >couple of heat sinks.  The biggest device can shift 60W with an >efficiency of 80-90%, which ain't bad (although it would flatten my >car battery in about half an hour). >  So-Called Cool-Hot boxes have been advetised for several years.  I recall Damark advertising them in a recent catalog.  Problem with the units is they do a sh***y job of keeping food cold/warm.  The peliter devices used just don't seem to have enough punch to keep up.  If you want something hot, you need to heat it up before you put it in the box, and end up hours later with food thats only moderately warm.  Same goes for cold items.  >Unfortunately the catalogue didn't list anything more than the basic >specs as a heat pump.  I imagine that you would get a back-EMF as the >temperature gradient across the device increases.  If so, presumably >its power decreases as the back-EMF increases, until eventually we >have a steady state with no current being consumed (assuming no >leakage).  If so, then the final temperature difference between the >two sides could be set by the supply voltage and nothing more >(although that would be a lousy way to control it). > >What I would like to know is: > >1: Are the above guesses correct? > >2: What is the open-circuit thermal resistance of a typical device? >   (I just want to be sure that my coolbox is not going to get warm >   too fast when I unplug it)   You'de probably be better off getting a good Coleman(tm) cooler and stocking up on "blue ice" blocks.  > >3: How does a Peltier Effect heat pump actually work?  It looks like >   magic! > >4: Why don't they use these things in domestic fridges/freezers? >  Same as above.  Not enough "punch" in them to keep/get things cold/hot. > >Thanks in advance, > >Paul. > >Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245 >--------------------------------------------+---------------------------------- >These ideas and others like them can be had | GEC-Marconi Research is not >for $0.02 each from any reputable idealist. | responsible for my opinions Mike Behnke             | Senior Tech/Advisor | Quid est illuidin aqua?? Fermi Nat Accel Lab     | Equipment Suuport   | Batavia, Il.            | Computing Div       | PISTRIX!!  PISTRIX!! BEHNKE@FNALF.FNAL.GOV   |                     |  My opinions are my own, not of the lab. So, if you don't like them, call
galen@picea.CFNR.ColoState.EDU (Galen Watts) writes: :  : Why can't he record it legally?  It may not be admissable in court, but : recording for personal use is legal.  If he wants to play it for his ham : friend, that's legal too, as long as he doesn't charge admission.  Yeah - I goofed - a slip of the mind. I must be getting senile.  ... deleted ...  : Hey Bill, where were you three weeks ago when all this stuff was posted : and dealt with?  Busy posting on about 20 other groups. I get to this one about once every three months or so.
Where can I buy blinking LEDs besides radio shack?      * Does anyone sell blinking LEDs with variable flash rate? (by voltage     I guess) If so, what hertz (pulse) rate are they adjustable or set to?       I'd like blinking LEDs that can be set for approx 5 hz, 10 hz,       15 hz, or 20 hz. Something like that... I'm interested in what's      out there for flash rates. I like the idea of LEDs with flasher       circuits already in them. I hate soldering ICs in general. Guess I      don't have a hell of a lot of patience.          Thanks,
Hi.  Our problem is the following:  We have to design an RF link for a distance of 250 m.  We're using standard RS232 waves (square pulses) as the modulating waves and the  carrier wave is sinusoidal.  The link has to be bidirectional.   We would appreciate any advice on the type of modulating techniques or antennas that we should use.  Please internet email us at:  007gjf3@witsvma.wits.ac.za  (Nando)                          or   007bww3@witsvma.wits.ac.za  (Warren)                          or   blumenow@underdog.ee.wits.ac.za  (Warren)  Thank you very much in advance.
In article <C5x3E6.3nx@athena.cs.uga.edu> mcovingt@aisun3.ai.uga.edu (Michael Covington) writes: >In article <1993Apr21.204556.21262@cronkite.ocis.temple.edu> camter28@astro.ocis.temple.edu (Carter Ames) writes: >> >>  Why does a lead acid battery discharge and become dead (totally unuseable) >>when stored on a concrete floor?   >>  I decided to bring the battery in from the lawn mower and the motorcycle >>from the unheated garage this year, *to preserve them* and I just >>went to use them and noticed that not only do they not work, but  >>they act like the two terminals are shorted.  I asked a friend >>and he said that you should never do that, 'cause it ruins them, >>but he couldn't tell me why. > >This topic was beaten to death a year or so ago. > >The concrete is not the problem.  > >Lead-acid batteries often fail from disuse (not being charged for a long >time), but there's no way the concrete floor could be the cause of the >problem.  The concrete floor accelerates the problem because it is a heat sink and a colder lead-acid battery self-discharges at a slightly faster rate. That's why the old wives' tale of sitting it on a piece of wood on the floor works to help keep from killing the battery as fast ---- it insulates the battery thermally. It you'll set the battery down on a piece of styrofoam, it will self-discharge even slower. The best thing would be to attach a small load such as a small transistor radio with the volume turned down low and leave it on constantly, but also trickle-charge it every couple days too to "shallow- cycle" the charge in the battery. Such mild "exercising" of a lead-acid battery is the next best thing to completely removing the electrolyte for storage. If you do remove the electrolyte, may sure you keep separate storage containers for each cell's electrolyte and put it back into the same cells when you refill the battery. This isn't so critical for a brand-new battery in a fully charged state, but will maximize the restored output of an older battery which may not be fully charged when you remove the electrolyte for    storage.
ifarqhar@laurel.ocs.mq.edu.au (Ian Farquhar) writes:  >In article <1993Apr21.081317.599@das.harvard.edu> squish@endor.uucp (Shishin Yamada) writes: >>The Atari 2600 used a 6502 CPU, just like their entire 8-bit line >>(400, 800,1200,1400, 1440, 130xe, 65xe computers, as well as the 5200 >>game machine).   >Wrong, it has a 6507.  For those who would like to know, the 6507 was a 6502 without IRQ or NMI, and with only 13 address lines (giving 8K memory space).  >It had one custome chip (not an ASIC in the sense that word is now understood): >the TIA (sometimes known as the 6526, although most other manufacturers list >that as the CIA complex interface adapter.)  TIA stands for Television >Interface Adapter, and it handles sound, paddles and the minimal video hardware >the 2600 possessed.  Didn't know about it being called the 6526 - thats the CIA found in the Commodore 64 (I don't believe this chip existed when the 2600 was around). The TIA was mapped into the bottom 128 bytes of page 0, and shadowed in the bottom 128 bytes of page 1. To get an image on the screen, you had to wait until the raster line your picture started at, load bitmaps for this line into the 'sprite' registers, tell them what x positions to take, how many duplicates you wanted, etc, then do it all again for the next line. This took all of the processor's time during the visible portion of the display.  >There was also a standard 6532 RAM, I/O, Timer (RIOT), plus a voltage >regulator and (if memory serves) a 555 timer.  That's all.  The RAM was mapped into the top 128 bytes of page 0, and shadowed in page 1. The 6502 has a zero-page addressing mode on most instructions that is both shorter and faster than the normal ones, so it is important on a machine like this to have the scratchpad RAM in page 0. Unfortunately, it also wants its stack to be in page 1 (the stack pointer is 8 bits, and the high byte of the address is hardwired to 1).  The IOT section was mapped into page 2 somewhere. 2 8 bit I/O registers (can't remember if each bit could be independantly set to I or O like the 6522 and 6526), and 1(?) 8(?) bit timer with a programmable prescaler (I think this was some power of 2). There were no interrupts in the system, so many games would set up the timer at some known time, go away and do something else for a while, then sit and wait for the timer to run down.  There was no logic in the box to do address decoding - the RIOT had at least 2 chip select pins (probably one active high, one active low), and I imagine the TIA was much the same. Various address lines were fed directly to chip selects. The 6507 likes to have ROM right at the top of memory, so the 2600 had to use ROMs with active high chip selects - not exactly normal, so some cartriges had a 7404 in them to convert this to the more usual active low chip select.
Here is a list I get when I was combing through some microfilm one day here at Drexel while completely board.  Most of these circuits are pretty easy to constuct and can be done by a novice. 	This is basically some stuff that could prove useful to you without having to sit down and either design or buy the stuff (not a good word, but I'm tired right now). 	Hope you enjoy!  	If you have any additions send them to me and I'll add them to the list .  They don't have to be from this particular magazine, they just have to be interesting!  	RADIO ELECTRONICS  Year	Month	Page	Article Name and/or discription ---------------------------------------------------------------------------- 92	April	31	Car Audio Amplifier (270 Watts) 	May	41	Midi Light Controller (Light control from music input) 		47	Solid State Relay  		50	Digital Altimeter 	June	53	Electronic Thermostat 91	February43	Audio Sweep/Marker Generator (frequency response) 	April	43	Line Power from 12 volts (12 VDC -> 110 VAC) (40 Watts) 	June 	39	Electronic Compass 	August	55	Speaker Protector 	Sept.	33	Solid State Tesla Coil 	Oct.	39	Vocal Effects/Mixer 	Nov.	58	Music on Hold (Play music for someone who is on hold on 				the phone) 	Dec.	47	THD Analizer 		53	Battery Tool 		63	Electronic Fuse 90	Jan.	35	Acoustic field Generator 		45	Phone activated Audio Muting circuit 	Feb.	31	Frequency Probe 		37	Radar Detector Tester 	March	31	Universal Laboratory Power Supply 	April 	33	Morse/RTTY Detector 		43 	Capacitance Adaptor (Capacitance add on for a DMM) 		46	Solid State Wiper control 	May	37 	Universal Descrambler (for a TV) 	July	31 	Digital Dashboard (for a car) 	August	41	Digital Pressure gauge 	Sept.	33	Vocal Stripper (take the vocals away from music) 	Oct.	37	Rocket Altimeter (model rockets) 	Dec.	33	Benchtop Frequency counter 89	Jan	55	Carrier-Current Audio transmitter (audio through your 				house's wiring) 		62 	Plasma display globe 		70 	Advanced Control System 	Feb.	55	Carrier-Current Receiver 	March	51	Hi-Fi Audio Amp for House or Car (High Power) 	May	41	I-R Extender (extender for Infra-Red remotes) 	July	31 	Light beam communication 		38	Digital Capacitance meter 	Nov	39 	R-C Decade Box  		43	Digital Compass 	Dec	37	Programmable Phasor Property Guard 88	July	41 	L-C Meter Part 1 	August 50	L-C Meter Part 2 87	Nov.	107	Electronic Combonation Lock 86	Sept	41	Stun Gun 	June	55	Click and Pop filter for your stereo (removes clicks and 				pops when you play old LPs)  -- From what I could see, you can order the circuit kits, finished or unfinished 	or you can order the parts that you can't get through a normal store
From article <1993Apr25.201129.1239@Princeton.EDU>, by fuchs@tsar.princeton.edu (Ira H. Fuchs): > Is there a readily available solvent that does a good job at removing the   > corrosion/encrustation that collects on the battery terminals (usually the   > cathode) when using alkaline batteries (or more accurately, when NOT using   > them for a long time)?   generally,  the corrosion is a signal that it's time to send them  of to the recyclers, but if you're that desperate or cheap try  baking soda and a wire brush. use gloves and goggles, please!
I have some MICE that have a chip numbered HM8348 and HM8350.  I have not   been able to find information on these.  Any help would be appreciated. mcole@nmsu.edu
AllMartin EmdeDMM Advice Needed  ME>From: mce5921@bcstec.ca.boeing.com (Martin Emde) ME>Organization: Boeing ME>  ME>I an currely in the market for a DMM and recently saw an add ME>for a Kelvin 94 ($199).  Does anyone own one of these or some ME>other brand that they are extremely happy with.  How do the  ME>small name brands compare with the Fluke and Beckman brands? ME>I am willing to spend ~$200 for one. ME>  ME>Any help is greatly appreciated. (please email) ME>  ME>-Martin  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. I have a metex which is some  made up name, as I have seen the same DMM with other brand names on it, I  bought it about 4 yrs ago for Aus$125.00 (convert that to US and you see  that it's definetly a cheapie.) So far it has proved to be accurate, taken  moderate abuse, and has many features on it (CAP, FREQ,Transistor check,  etc). I am very happy with it and would definetly not buy a fluke just for  the name. Hope this helps.
In article <26APR199315293014@utkvx.utk.edu> iturriag@utkvx.utk.edu (Mr. Y) writes:  > I am not quite so sure about the illegality of using a regular American phone > on your home system. I vaguely remember a few years ago, when "Deutsche > Bundespost" split into Postdienst, Postbank, and Telekom there was some > discussion about a new regulation. I know that cordless or cellular phones > still have to be approved by the Telekom, but does that hold true for regular > phones? In my areacode in Germany (2234 - Frechen, near Koeln) you can use  Yes, it does. All the equipment has to have that Telekom approval number to be legal. What has changed is that you can buy the equipment somewhere else. I'm pretty sure the same holds true in Sweden (at least when I read some information on it about tweo years ago). And BTW I do know that most of the lines in Sweden can handle tone-dialing, just don't be sure that all can.
In article <1993Apr13.164924.2606@wuecl.wustl.edu> dp@cec1.wustl.edu (David Prutchi) writes: >Can circuits found in electronics magazines (with no patent disclaimer) >be used legally as subcircuits of a commercial unit ?  There are two issues here:  copyright and patent.  The magazine article's contents are copyrighted, and may not be reproduced, translated, etc., without the copyright holder's permission.  However, this does not cover the *ideas* expressed, only the form of expression.  Copying their circuit diagram or PC-board pattern is copyright infringement.  But it's unlikely that they could stretch copyright far enough to claim that the circuit design itself is copyrighted.  So long as you draw your own diagrams and lay out your own boards, copyright shouldn't be an issue.  Patents are different.  The author does *not* have to give you any warning that the design is covered by patent (although it would be sensible for him to do so).  In fact, it's possible that *he* was infringing on someone else's patent without realizing it.  Ignorance of the patented status is not a defence against infringement, although it might reduce the damages a court would award.  However... unless there was something seriously novel about the circuit, almost certainly it is "obvious to one skilled in the art" and therefore unpatentable.  Routine engineering is not patentable; patents (in theory) cover only inventions, ideas that are genuinely new.  Caution:  I am not a lawyer.  Consulting a professional would be wise if significant amounts of money are at stake.